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.
Reddit lets you sort by Best (default), Top (highest raw score), New/Old (chronological), and also Controversial - no add-on required. It's right above the first comment.
"Best" is a time-weighted blend of scoring, so that well-voted but late contributions are more likely to be visible despite fewer overall votes. Certainly not perfect, but helps bias away from "first to comment wins"