Yeah, that's what bothers me. Feels like people romanticize pre-Musk Twitter, when in reality, its always just been complete garbage. Musk's Twitter is certainly worse in some ways, though that isn't saying a lot.
Overall, Twitter just sucks. Use other platforms where possible.
Brave is not spyware. That website you linked is horrible and full of misinformation. They also claim that Firefox, and even Tor Browser, are spyware. They act as if any and all connections a browser makes are automatically bad and used for spying/tracking.
I won't disagree with the other criticisms of Brave that you made, but just wanted to point that out. That website is just highly unreliable and makes verifiably false claims about the browsers it reviews.
What shell would you recommend? 🤔
I usually just create a burner Proton Mail account in that case, and keep note of its details and purpose in my Password Manager so I don't forget.
Great, then you probably don't need SponsorBlock, to my knowledge the extension only works on YouTube's official website.
I have some accounts saved in my previous browser e.g. Google, Discord, Spotify etc. that I don't use really much, but require them regardless
I personally keep an entirely separate browser profile for Google, and another separate profile for Discord. Just further isolates things even more than Firefox/Librewolf already does, plus extensions and tweaks and such can be customized as needed per profile, etc. Profiles can be accessed through about:profiles in the browser FYI.
I use uBlock Origin and SponsorBlock as the only extensions
That's pretty good. The only other extension I'd recommend is Skip Redirect, its pretty useful and improves privacy, also recommended by Arkenfox.
If you want a more private way to watch YouTube as well, you can try Piped. It proxies all connections to Google/YouTube (so never directly connects to them and their servers), plus removes ads, tracking, and telemetry. It also has SponsorBlock, Return YouTube Dislike, and more built-in, so would make the SponsorBlock extension unnecessary too. Piped does have its downsides, but I'd recommend trying it and seeing what you think.
If Piped isn't for you, my recommendation is to just watch YouTube either logged out, or signed in with my suggestion above of using a separate profile if you really have to.
I installed Mull in my phone in the hope of pairing it with Librewolf while avoiding creating a Firefox account if possible
You will need a Firefox account for syncing. The good thing is the data synced is encrypted so not even Mozilla can see it, and Mozilla does generally have a good reputation with things like this, so I don't think its a major concern.
Another general tip I can give is to set the browser to clear cookies and site data on close, and just make exceptions for sites you need to stay logged in to or set preferences on. This helps massively in preventing sites from tracking you and when, if, and how you use them, it also prevents unnecessary storage space being taken up on your drive, etc.
I understand how you feel, let me know if you find anything. I'm more left leaning myself, but I'm also not a fan of echo chambers and it gets pretty tiring and annoying seeing the same stuff over and over again. At the end of the day, I just wanna see an open, fair, and balanced discussion. The Fediverse is undeniably very left leaning currently, which is surprising to me since you'd think the anti-censorship design on paper would appeal more to people on the right who are against big tech and censorship, but I guess not? It's interesting.
There's so many I could list, I'll just mention 2 underrated ones I don't see mentioned as much:
LibreTube - Best YouTube client imo, has a very nice and modern interface, proxies videos through Piped for maximum privacy (No direct connections to Google are made), No ads/tracking, SponsorBlock + Return YouTube Dislikes, support for downloading videos, etc. It's everything I'd want and more out of a YouTube client.
URLCheck - Excellent app that allows you to preview what a URL is before you click it, includes tons of features such as scanning for malware, removing any tracking parameters, upgrading links from HTTP to HTTPS, etc. I can't recommend this app enough for the security, privacy, and general peace of mind it gives you.
You can easily change launchers on the Shield and remove all of Google's nonsense through ADB as well though, unlike Amazon who locks down the OS very tight. Plus like another commenter said, you can just flat out install LineageOS and you're good.