I'm troubleshooting an issue with slow logins on a Sitecore instance.

As part of that investigation I've found a number of posts - such as Sitecore client and logon is very slow (properties table AGAIN), Sitecore.Web.Authentication.c__DisplayClass5.b__2(Ticket ticket) +52, and an answer on Sitecore Client login Timeout error - Azure PaaS - that point to the Sitecore_Core.dbo.Properties table and rows with a Key of SC_TICKET*.

Looking at our instance's database I see a number of rows, however there are no new records since we upgraded to 9.0.2 (July of last year).

Keeping in mind the usual best practices when touching a third-party system's database, is there any issue with purging these keys from the database?

Given that no new records are being added after logging in, are tickets in 9.x+ now stored in a different table?