For the most part, yes. There are some days like 4th of July and NYE that it's blocked. The parking benefit used to only be good on days your pass was valid, which always seemed a little unfair since it costs the same. But some time around when it passed $119 they changed that policy.
I just checked the AP terms, and they totally changed since last year. They now only address the renewal of the parking benefit. But I've parking in TS on a blockout day as recently as 2 months ago. If you they do try to charge you, the convention lot is a little cheaper than Disney lots.
Last time there were signs at the Disney lots asking Expo attendees not to park there, but to use the Convention Center lot. CMs at the parking booths asked if you were going to Expo or to the parks.
They were letting people park there for Celebration. They did convention parking in a separate area closer to Harbor. I wonder if D23 has more attendees than Celebration.