Another in the "still online since the '90s" list is of course the original "Space Jam" promotional website. When the new movie started being promoted they reused the domain, but obviously somebody at WB cares about internet history because they left a link to the original on the front page and moved it to a subdirectory. https://www.spacejam.com/1996/
They definitely did. They even updated the 1996 page over the years with the latest and greatest in internet analytic tracking.
Accessed via https://www.spacejam.com/1996, the landing page contains a Google Analytics 4 tag. GA4 was released in late 2020. Strangely, the GA tag is absent if you navigate to the (otherwise identical) landing page on https://www.spacejam.com/1996/jam.htm.
There's also an old Omniture tag, with a copyright notice from 2008. Omniture was acquired by Adobe around that time, and was renamed to Adobe Analytics almost a decade ago.
The other pages have Google Tag Manager (first released 2012) installed. However the container fails to load, as either the account or container has since been deleted.
I'm slightly surprised there's no old Urchin tags floating around, then the site would be a kind of museum of web analytics services.