I know it's in its infancy but the great thing about Reddit was I could search any niche topic and guarantee there was a subreddit setup for it.
Obviously this is solved by more and more people using Lemmy but I personally can't see Lemmy appealing to the the masses. Depending how active the communities become I can see me using Lemmy going forward but I don't think it will be the "One site for everything" that Reddit has become but rather 1 of many sites I check going forward instead