Of 12 flights so far this year:

3 upgraded with miles, 1st class full
5 upgraded with certs: 2 1st was full 3 flights with 2 or 3 empty 1st seats (on narrow-bodies)
2 not upgraded due to "gallentry," but plenty of empty C class seats on 777s.
1 not upgraded due to 9C seat selection on red-eye, but seats in 1st were available
1 did not clear cert upgrade list

So I'd say solely from my experiences (on both short-hop domestic and one trans-atlantic), that upgrades have been plentiful and even open 1st seats more flights than ususal!

However, your logic would seem to make sense that many non-requalifiers are taking a last gasp, and that people are using the comped certs from requalifications...maybe I've just been lucky...