I like “active” sort specifically because it biases new comments on posts, instead of new posts, so that if people keep talking on a post, or if an old post gets an unexpected rush of comment activity, it’ll stay on my homepage. It makes the homepage move slower, makes post success much less dependent on its exact timing vs peak lemmy usage, and it lets discussions last longer, and lets people participate in discussions longer than immediately after the post goes up. Gives everything a more patient feel.
And imo may indeed mitigate the problems some are fearing with megathreads based on how they could be on reddit sometimes.