It means you aren’t suited to run a public facing business. There’s nothing wrong with that, but speaking as someone with a lot of social anxiety baggage there are things I’m equipped to do well and things that I’m not. I shouldn’t let that stop me from opening a business if I really want to, but if I simply don’t want to deal with the social rejection elements I have to accept that I’m better off letting someone else run that side of a business.
As for the non-business elements of your question, all you can really do is conduct yourself in a way that you don’t believe you’ll find yourself regretting later. If you say something in a public place, especially online, consider it part of the public record. It can and will come back to bite you later. Assume your [morally positive family member here] is always watching.
As others have already covered, everything we do comes with risk. Some people go through life without spending much thought on those risks, and if they’re lucky they never have to deal with these things. Others let it weigh upon them heavily, and it’s fairly evident that you fall into the latter camp.
You’ve caught on to the general theme though, which is that the more of yourself you put out there needlessly, the greater a possibility for negative things to happen as a result of that. I’m not going to ask you to wave a magic wand and become the type of person who doesn’t worry about those things, so here are the best compromises:
Quality over quantity with your friends. Find some good people you can be yourself around, and don’t stress over having fewer people that you hang out with than others. It’s not a competition and it doesn’t make you an inferior person.
Minimize how much you “put yourself out there”. The internet wasn’t around 25 years ago, and when it was young it was common sense to use an alias on the internet wherever possible. Use different nicknames on different websites to minimize the ability of casual bad actors to link your identities between different social forums. The possibility of database leaks doxxing the e-mail address you signed up with is still there, but thwarting the low effort attempts does a lot on its own. You can go through the effort of registering with different e-mail addresses as well, but there is a point of diminishing returns here and you need to decide where to draw the line for yourself.
Remove yourself from online discussions when it’s healthy to do so. Assert your opinion, clarify your points if they need clarifying, and move on. Turn off notifications once you’re past that point. Winning arguments on the internet is not realistically a thing that happens, and notifications on your mobile device from an argument will needlessly pull you back into a place of anxiety. Considering how little those mobile notifications contribute to your positive frame of mind, it’s best to be rid of them completely if you ever find them having a negative impact on your day to day life.
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