Sorry, lengthy answer because difficult question.

How I stop worrying about Nvidia and deal with it

I have voiced my frustration with Nvidia elsewhere, and there are still annoying bugs, that no one can fix because it's proprietary, but I live through it because I love everything else on Linux.

I like that using Linux makes me more careful, I learn things all the time, I stopped feeling entitled to many things. The idea of a software is changed dramatically, it's a code as an MVP, then built up slowly based on what the dev wants, as they often use the projects they maintain themselves, or contribution and requests from their users, which is so much more sustainable than what you get in the for-profit, proprietary domain.

For this reason, I avoid negatively talking about small community-driven foss projects on the internet, because I can be actively constructive by being the change I want to see, whereas on Windows I would be stuck with a subpar product with no source code to investigate.

I think in your case, and please don't take it personal, we don't know each other, I don't know what you're going through or how you are as a person, I'm making a small judgement based on word choice here, but calling something "trash", even after you know it's made by someone who probably wants to use their streamdeck on Linux (just like you) is quite a hostile thing to say and will invite some hostility back. I would retract it but you do you.

Caveat Now, some foss devs are whirling shit against each other all the time on their personal blogs but that's within their own dev-dev domain, not user-dev domain. Say hypothetically if you start contributing to streamdeck-ui and the Dev starts being an AH then you can fork it and maybe then go online and vent.

Why forums appear toxic

I can admit some forums read very blunt and impatient, like BBS Arch Forum, but they only exercise patience when it's a big they've never seen before, and will ask you to paste all sorts of command outputs to troubleshoot, otherwise, they are quick to recognise if the problem have been encountered, and will typically send you to the link of the solved post or tell you to RTFM because it's somewhere in the manual. To be frank, this behavior I can understand and have no issue with.

On more general forums like this one, it's often the case users ask question that they can do some precursor research and once stuck (no mention of issues anywhere, no similar thread), then if they do post, I've only seen poor quality comments like "works for me" or "same but idk the fix", since the commenters will have to do the same searches the poster did and come to the same conclusions (here, it's nice to send them links you researched to save them a few clicks). I've made similar posts with great details on what I tried but it's still broken. If no one knows, then I open an issue.

Now, if they didn't do research beforehand, commenters will look it up and then have to correct you but they might feel annoyed because why didn't you do it before posting. Not everyone will be bothered by it. But I do feel like a search or two beforehand will bring a much more fruitful discussions.

I won't defend inflammatory toxic language, but I don't think there are any here present in this thread, it's just a lot of "AcKtuaLLy" comments, but those were done to correct you and if I were you I don't think I wouldn't really get all defensive. I pride my time using Linux, and other commenters probably do too, but we all started somewhere so we know when we see the "I didn't do my research but gonna post anyway" attitude. If one likes doing this, just get ready for people who want to correct things, I guess.

It's a kind of tough love here where it's heavily encouraged that one does their own heavy lifting instead of relying on others. At least that's what I've observed. It might be negative, but it's better being spoonfed. I've managed to avoid such negativity by trying to exhaust all options before posting for help. I learned so much and I hope you find a way to approach Linux that works for you! There are still others out there who aren't jaded by newbie questions and still will help, just don't expect their language to be nurturing.

Also, please consider ignoring internet points, they do nothing but makes you feel distressed. In places like this it's a bit like on Hacker News where it's to show if a comment is helpful/ constructive, or not. It's not personal.