Some people seem to be interpreting this to mean 11 million comments per day. I think it means the numbers are updated daily.
The numbers also don't make a lot of sense to me. Front page of lemmy.world says 620,000 (local origin) comments. And Lemmy sequentially numbers the comments for an instance, mixing both local and federated and the recent numbers look like 2,122,067. Lemmy.ml says 253,000 on the front page, and their index key is showing 2,321,959 for a comment made today. I have to imagine that these two servers are subscribed to a lot of stuff (including each other). I'd be surprised if there were more than 4 million unique comments in Lemmy. And there would be some kbin messages in the Lemmy.world index.