Lemmy’s federated structure makes it easy to block the instances which don’t moderate the nazis or tankies or anything else away to your satisfaction, while Substack is a centralized platform which has chosen to not only allow, but actively encourage and reward its nazis.

So, any such problem on Lemmy is “better” because we can all (as individual users, and/or collectively as instances) deal with it as we like instead of bowing to Substack’s decision to be a nazi bar for all its users.