He’s kinda right, or for me at least. Lemmy is in no way a replacement for Reddit. I don’t really think it should be, but I bet a lot of people that try lemmy made an account in the assumption, or hope, that it would be a replacement for reddit.
It also has a total different vibe I think. 5-10 years ago I would have loved this place, currently it feels a bit of a too young crowd for me (34 years old).