IMO that should be an option (twitter style, reddit style or chronological style). Wonder if there is browser extension for it.

That said discord kinda does it and I just can't stand it. Unusable to me.

Discord threads are just an addon on top of a chat. It's not really a real discussion. And the discord discussions (or whatever it is called) are again flat IIRC? Slack threads are flat. Both are chat platforms first and foremost I would say.