Between types or classes or generations of websites
I’m suggesting that we link all websites that exist in a unnamed class that includes the attributes of websites published prior to 2003 (as an example criteria based on when wordpress launched).
What would you name such a class other than Web 1.0 or old web or some such
"Non-Wordpress?" Otherwise that's just an arbitrary cut-off. If you want to convey something, you need to state it in English. "Pre-Wordpress" is another possibility.