The fact that not all Capitalists support the Federal Reserve doesn't change the fact that the Federal Reserve is an inherent expression of Capitalism.
The problem is back in the late 90s and 2000s talking about the Federal Reserve at all on the Internet was largely monopolized by Paleo-Conservative and Libertarian Conspiracy Theorists, with literal Nazis from Stormfront sometimes worming their way into those communities.
I don't agree with the anti-Breadtube narrative of Caleb Maupin and Peter Coffin, but I do agree that Breadtube in many areas are poor ambassadors of Communist Ideology because they are Anti-Conservatives first and foremost, they say they know the American Right's conflation of Liberalism and Socialism is wrong, but to them the difference is often just a matter of extremes, to them Liberalism is synymous with Centrism and Socialism is about being even more opposed to Conservatism then the Liberals are. The truth is much of the American Right unintentionally agrees with proper Socialism on some issues, not as many as Maupin and Coffin thinks, but still they do in fact agree sometimes. This Breadtuber problem is why you have an epidemic of people online who think it's okay to call yourself a Socialist while supporting Gun Control, and it's also why we now have pseudo leftist defenses of the Federal Reserve.
There are three reasons to oppose the Federal Reserve system. Well there is a fourth which is abolishing Money altogether which is the long term goal of Communism but that really can't be achieved without changing our economic system altogether. Within the context of having Money there are three reasons to oppose the Federal Reserve, two are inherently capitalist and/or anti-capitalist in a way that is reactionary, the third can also be co-opted by liberals or reactionaries but is at it's core what Socialists should believe about Monetary policy.
One reason is to oppose "Soft Money" and demand a return to the Gold Standard or something like it, the most well known form of this is the Austrian School. Now I find it amusing when modern online Leftists act like calling for the Gold Standard is an Anti-Semitic Dog Whistle, because when the Gold Standard was what we had all Anti-Semites without exception opposed it, one of the sad blemishes on the classical American Populist/Progressive movement was how many people couldn't stop themselves from bringing their Anti-Semitism into their opposition to the Gold Standard. You see Anti-Semites see Gold as inherently a tool of the Jews. George W. Christians was a prominent American Nazi of the 1930s who's platform included Abolition of the Gold Standard.
Nazis only really started opposing the Federal Reserve when Eustace Mullins published his book on the subject in the 1950s. The NSDAP Regime didn't abolish the German equivalent but simply put Party members in charge of it, one was literally a reappointment of someone who'd already ran it before. Meanwhile in Italy it was specifically the Fascist regime that first gave the Bank of Italy the exclusive right to print the currency.
Breadtubers also don't seem to get that not all opponents of the Federal Reserve are Gold Standard supporters. In Sarcasmitron's video on the subject he talks about Trump era conspiracy theorists being unable to reconcile their inherently Hard Money ideology with supporting a Soft Money president and even being unable to see the contradiction. But Blackbigeonspeaks endorsed the soft money policies of Lincoln and JFK and based his narrative on the documentary The Money Masters which is an explicitly anti-Gold Standard documentary, I know this because I've watched it more times then I can count, originally over a decade ago as someone less critical of it then I am now, but I also rewatched it more recently with my new perspectives in mind. Sarcasmitron however seems to have not heard about it till it came up in an Alt-Right YouTube video he wanted to debunk and then just sorta skimmed it. Same with Munecat, I actually endorse most of her anti Crypto video, but when she starts throwing in the Federal Reserve stuff she clearly didn't do as much research.
The Money Masters film makers are like a lot of people in the old Progressive movement who opposed the Federal Reserve's creation even though they had just spent decades calling for Soft Money, they feel that the Federal Reserve doesn't undo the problems of the Gold Standard but rather makes it worse.
The second reason to oppose the Federal Reserve is to be a supporter of Paper Money but feel it gives the government too much regulation of the Economy. These people may have been fine with the original Aldrich Bill before Wilson and Bryan added more government oversight to it.
The Chicago School is often confused with the Austrian School, but the core difference is the Chicago Boys are not Gold Standard supporters. Some of them are fine with the Federal Reserve in fact many heads of the Fed have been Chicago Boys, but those who do oppose it fit into type two.
The third reason to oppose the Federal Reserve is feeling it doesn't regulate the economy enough. When Marx made creating a Central Bank one of the planks of the Communist Manifesto, he was NOT referring to anything like what the Federal Reserve wound up being, nor the Central Banks that already existed in the Western Capitalist powers he was criticizing like England and France. He's referring to a Central Bank directly controlled by the Proletariat (The Working Class).
The Money Masters seem to also fall into the view that the Federal Reserve isn't regulated enough, that alone wouldn't make them Socialists, the movie gives me little to go on regarding their economic views outside of specifically how Money is printed. The movie is wrong about certain historical subjects like repeating the Nathan Rothschild and Waterloo myth. But it seems to Sarcasmitron it was inherently Anti-Semitic to mention the Rothschilds at all (yet his own making a secret supervillain out of Milton Freidman in his Covid video is fine), I however was shocked when I first watched it that they ignored Jacob Schiff keeping their history of American banking focused on J.P. Morgan who was a 100% Gentile, but that is more accurate Morgan was in fact way more influential.
Scarasmitron says it would be a bad thing to have the Printing of money directly controlled by the Government, and cites Turkey as an example. That's because Turkey isn't a democracy, neither is the US of course but what I am calling for the US to do is have the printing of Money directly regulated by Congress, not monarchically controlled by a Presidential appointee.