When you lock specific page types (FREE version) or specific products/collections/pages (PAID version), it makes sense to display the login form with a Create an account button or link for non-signed-up customers.
However, always remember to enable the accounts. Otherwise, the Create an account link will end up to be a 404 or be redirected to Homepage.
To check, please go to Settings > Checkout
Under Customer accounts. choose 'Accounts are optional'
Hope the answer is helpful. Let us know at email@example.com if you need further help.