v3 show comments by default gone
There are few reasons behind that:
- Takes too much space when there are lots of comments.
- Slow page loading.
So, we decided to keep it hidden by default.
priard commented on answer

ptrcklpzg commented
I’d like to see this feature coming back to. Loading a handful of ‘teaser’ comments asynchronously and a “more” button would be perfect.

Fred - FLQ commented
I completely agree with ptrcklpzg: load the first comments and a “more” button. It would help for posts with many comments and would be perfect for those with just a few ones. 😀

dyba03 commented
I completely agree with ptrcklpzg too!
priard commented
Nonetheless there should be a option to show last 2-3 or so, and button / link to show them all, with ajaxed pagination if there is to much. That way there is just better UX overall.
Is it possible to show them by a filter? Can you post some advice on how to show comments by default? I would like to do that.