As a moderator of /r/kindle, I can reveal that in January 2025, less than 1% of our visits were from users still using Old Reddit.

It does mostly attract users who aren't as technically minded as users on HN.

iOS Apps - 36.65% | Mobile Web - 24.85% | New Reddit - 24.37% | Android Apps - 13.30% | Old Reddit - 0.82%