In case anybody runs into this (most likely me at some future date):

I had a customer who upgraded their server today and the SQL (even outside of Dataflex) was painfully slow. A simple SELECT * statement which took 1 second on the old server took 90 seconds on the new server....

The IT tech just sent me an email with the answer:

As for the slow issue, I found that a VM hosting SQL should not have dynamic memory checked off. In case you run into this again.