It is by choice. Prominent developers made that choice because they thought it might eliminate a lot of the popularity incentives reddit creates.

Now I don’t agree with that choice, but many others here do. I don’t think this solves the incentive issues but just makes instances a bit more of a wild western and requires moderators to do more work figuring out what to make of an account.

Maybe it would be great if this is still an option you could turn on / off per instance or something.