I put a simple search with only body type and height in.  The results came in by most recent date.  1st result reviewed 1month ago.  by the time I got to the eighth review the results came back with last review 3 years ago. No website or ad location for the provider.  Are there a lot of "stale" provider listings on ter?

Unless a provider is delisted/removed for a reason, they’re here forever. There are many very old profiles who have no reviews way longer than 3 years ago. There are ones that are from over 20 years ago.

unless her ad link is no longer good.  She could have changed to a no-review policy during Covid like a lot of providers did.  Generally, if her ad link is still good, she is still accepting business.  Otherwise, you will see a "Report New Link" message where the link should be at the top of her profile.

I have found that on free escort listing sites, girls who retire may not delete their page.  They just walk away.