I’ve tried to express this a few times online and fallen foul of offended introverts - my observation is that some people like to use the label of being an introvert as a shield or justification of (their dissatisfaction with?) their shy or antisocial behavioural traits.
If we replace people with ice cream, I think it works out something like:
* Social anxiety: I'm afraid I will choke on the ice cream.
* Introversion: Ice cream is fine but I don't really enjoy the flavor.
* Anti-social: Ice cream tastes gross.
These all manifest in the same visible way — avoiding ice cream — but the causes are distinct.
From my perspective (as an introvert) I would replace the "Introvert" line with:
* Introversion: I may or may not enjoy ice cream, but eating very much makes me exhausted. (Or "I feel full after eating just a bit".)
From my perspective, your analogy makes the very mistake that the grandparent comment brought up: conflating introversion with not liking social interaction.
Well yes and no. Socially, that's nobody's business indeed. Professionally, that can be a problem or at the very least a weakness. Social relationship are a skill, being bad at it isn't neutral.
Sure you can be wanting to avoid social relationships while being good at it, but I doubt this is any sort of common.
A lot of the learning was due to the need to communicate at work (e.g. giving complex presentations / demonstrations to challenging audiences) and also exposure to life situations that helped me realise that a presentation going wrong really isn't the worst thing that could happen to you.