>Given how long this "REAL ID" standard has been in effect, why have the non compliant IDs not expired yet? Do some states not issue REAL ID compliant licenses?

It's only been in effect for a short while, then we had COVID. It took them two decades to even get it live.

Some state licenses don't expire for 10 years. Americans will avoid trips to the DMV until it's absolutely necessary to go. YMMV on if your local one is well-run and efficient or a madhouse with long wait times.