>So you're asking how to do it without a tool that was specifically designed for that purpose?
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.
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?