Look here: https://github.com/jj-vcs/jj/discussions/ — by default, sorted by last activity. But you can also sort by newest, or by votes.
For comment threads, look at e.g.: https://github.com/jj-vcs/jj/discussions/5509?sort=old — sorted by time, by default. But you can also sort by upvotes.
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The forum software I'm developing, https://www.Talkyard.io, is also threaded, and can sort by time or by votes. (Both discussion topics and replies.)
F.ex. go here: https://forum.talkyard.io/-9qb49/solving-problem-first-comme... and scroll down to the replies section and click `Oldest first` to change order.
In addition to oldest/newest/"best", you can sort top level comments by time descending, and deeper comments by time _ascending_ or by votes — creating a kind of "micro blog feed" where each top level comment is the most recent "micro blog post" — but replies don't have to share the same sort order. "Newest, then popular" and "Newest, then oldest" I call these sort orders.
Also click the "Recent posts" in the upper right corner, to see the most recent comments sorted by time descending.
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Anyway. There's people who think the hybrid approach you mentioned is an good idea.