No, it's not wrong – you're conflating this with another issue. User enumeration attacks are real and bad. A better solution to that would be to not leak this

No, it's not wrong – you're conflating this with another issue. User enumeration attacks are real and bad. A better solution to that would be to not leak this information when trying to create an account, instead. Since most sign-up processes seem to require email confirmation anyway, nothing is really lost there. Of course, if you don't require email confirmation, then go right ahead – you'll have to use other approaches to avoid enumeration (like rate limits), but then you should be doing that anyway.