I don't believe I'd ever heard of foundry USA prior to seeing it as just another listed pool on taprootactivation.com/taproot.watch. I don't know anything about who operates it.
Foundry USA is just another name in the Digital Currency Group's "portfolio" they own it just like they own Blockstream and Grayscale.
But fortunately, even if someone managed to live under a rock and miss all that-- if they don't like taproot, for whatever (probably confused) reason, they don't have to use it. How someone chooses to manage their own Bitcoin should be no ones business but their own.
If you into this taproot thing and you really want to merge it why the hell you not forking Bitcoin and distributing your version? What prevents you from forking Bitcoin? Egoism that you are a contributor to "Bitcoin Core"? Is that why you don't wanna fork it?
If you don't like Bitcoin how it is maybe is time for you to simply stop using it!