Are you really saying you don't use PayPal? I presume you have a job; your job probably uses Slack (or Teams) at the corporate level. You're never streamed anything? You're not coming from Reddit? You don't use Wikipedia? Or Spotify? Or reCAPTCHA?
I most sincerely doubt that you've never used any of those, all of which run on tech that Facebook built and helps maintain. And I'm not even mentioning the countless small places that use things like React. I'm not joking when I say you literally cannot use the modern web without bumping into a website running React, which was - again - created by Facebook.
Maybe you think the things I mentioned are "apps" - they're not, to be clear. They're frameworks. You generally have no idea you're using them, because it's something that gets setup by the folks building the website. You don't directly download React.js; you go to Discord.gg and Discord will download React to your machine and run it to display Discord. Same thing with Wikipedia - you go to Wikipedia, it uses HHVM to show you the page you want.
If you knew all that already and still think you don't use tech run by Facebook, then your ignorance of how the web works is shocking.
I also think you're struggling with the concept of "Meta doesn't want the EU to come down on them." They will never extend the network in a way that breaks apps, and they can't extinguish it because both of those would make them "gatekeepers" under EU law - the thing they're trying to avoid.
You have to understand that - as much as I dislike capitalism - it is what drives consumers. Linux is the better OS than Windows. That's proven by basically everything running Linux... except consumer PCs, which are usually Macs or Windows. Because Linux doesn't advertise itself like they do, not really.
The way for the fediverse to grow is to get corporations to embrace it. The more corporations that embrace it, the less likely it is that any individual corpo can extend/extinguish (assuming they ignore the EU for some reason). Corporations means regular users, and regular users means normalization, which means a healthy and growing fediverse.
Rather than trying to get a big place to reject this at all cost, maybe you should move to a small place like Beehaw that will more readily accept your worldview.