If that's what paywall means now then sorry for the noise. :)
I would disagree with their assertion that requiring an account is a paywall. I mean, it's in the name... if you don't have to pay, it's not a paywall. A barrier to entry, sure, but a far easier one to overcome than entering payment details.
So a paywall. I agree it's a annoyingly misleading term for the concept and would be happy to hear better alternatives[0], but I haven't found one yet.
0: like eg "passphrase" instead of "password" or "assuming the conclusion" instead of "begging the question" for their respective concepts