I was merely acknowledging that there are two extremes to this mental struggle: loneliness, and people who are overwhelmed by having too much contact.

And that's the problem. While those two extremes do exist, this post is not about people overwhelmed by having too much contact, it's about literally the exact opposite. OP made this post looking for support and validation of the loneliness they feel, and your first response was essentially "Yeah that's sucks for you, but I and many other people desperately crave the thing you suffer from". You're not wrong, the issue of people feeling overwhelmed is an equally valid issue, but there's a time and place to bring it up, and this post wasn't it.

My piece of advice is if someone presents an issue to you(or in this case, lemmy at large) and is looking for support or advice on the issue from you, avoid contrasting their issue against other issues at all costs. No matter how well intentioned you are(and I DO believe you were well intentioned, fwiw), at BEST it will come across as "that sucks but others have it worse" and at worst it can come across as "that's not an issue most people have, so thinking it's an issue means you are the problem".