It’s hard to tell because the graphs aren’t labeled very well, but it looks to me like those graphs for comments and posts are the total numbers, not the numbers per day. In my anecdotal experience, there’s just no way lemmy is already getting as much new comments and posts as reddit, it’s just not that busy.
Edit: Oh wait, I see they go down at the end. Hmm, I wonder if they’re double counting posts and comments then.
I haven’t been having issues with my lemmy.world account, other than the occasional slow/failing to load page, but that gets fixed with a refresh.