Earlier quoted context omitted.
>The show/hide design pattern is annoying, IMO. Hmmh, I don't know how to make it better. It's really challenging to do it without JS in the first place. Do you have any ideas?
So you're asking how to do it without a tool that was specifically designed for that purpose? I really don't get the hate for JS these days.
Yes, you are correct. This is a hobby project of mine, and one of the goal was to make old.reddit.com like UI without no JS at all. That's what I will do.
>I really don't get the hate for JS these days.
Unnecessary Javascript bloats websites, hogs system resources, enables surveillance, hinders accessibility that’s native to devices and clients, and introduces vulnerabilities. https://nojs.club/
Of course in this case using JS to hide/show comment tree wouldn't really be that bad, but works fairly well without it. Not many have complained.