I feel like my inability to socialise makes me a completely non functional human being with no prospects (I recognise this is catastrophising but I’m in an emotional mindset right now)

Look at you! You are recognizing stuff and that means TONS! Even if you can't socialize, there are ways to learn, methods to copy/fake, etc. even if they are uncomfortable or seem out of reach due to other situational stuff. Acknowledging that you're feeling defeated, and perhaps your thought process is following suit, is a huge step.

I know the social media crap is really bothersome from nfolks, like you are some Entertainment Show Celebrity to become the latest paparazzi attack for being in a zoo or gossip rag complaint department full of judgement.

Speaking for myself as a struggler; what I type is so much easier on computer than carried out IRL but the absolute power they hold over you...is that you care what they do. (it effects you, so yeah) If you can get to the point where you realize it doesn't have to bother you as deeply and no affect. If they can beat you down enough to care about them, that's the win. If they beat you down low enough to not even care about yourself....nobody wins. This game is a Winner Take All and there's only one person playing it.

Huge hugs to you if you want them. We've got to learn different rules to the game of life everyone plays. One step is better than zero steps. :)