reddit is about the same in my opintion, but I do see a lot more activity on the lemmy side. I think its a combination of:
Less rules around communities. The barrier of entry is much lower here to post, and things dont get auto-removed because of trigger happy mods.
2% of users post 90% of content. And a lot of them moved over to lemmy.
Servers can be brought into existence and removed at will. This may seem like a bad thing, but what it means is that the best lemmy servers can evolve and be successful in a way reddit cant. Some have different modifications to make them more user friendly, some have excellent uptime, etc...etc...
People from mastodon/misskey/other fediverse instances can comment/post. Even if that is not what a vast majority of us do, it does help the numbers and will continue to help engagement.
Also to @Blaze Do you know if the sats above take into account the generally banned instances of lemmy? I know that a lot of instances earlier this year decided to become de-federated from the general fediverse. Do you happen to know if the website take into account those servers?