To some extent they seem to do. For instance I had forgotten to update the WHOIS record for phone number when my number had changed and after some months I star

To some extent they seem to do. For instance I had forgotten to update the WHOIS record for phone number when my number had changed and after some months I started getting reminders whenever I logged into my registrar's site that the phone number was not reachable and that I need to update it. But no emails, and certainly no paper mails regarding this. But no enforcement. Nothing happened even though I dragged my feet updating my phone number for a considerable time.