Pr 2023 stuck on 100% export - 16" M1 Max, NVME SSD

As per title. Autoupdated latest everything. 2021 16" M1 Max Macbook Pro. No spinning disks whatsoever. Boot off internal SSD. Footage on Thunderbolt 3 NVME SSD. The absolute fastest everything. 30-second edit using 25fps PAL H.264 footage in 1080x1920. Cleared cache. Fresh start (not "shut-lid for a week" or anything). The disk is not busy. The CPU is not busy. Everything else in the background has been quit. Spinning beach ball on Premiere.

The export takes 5 seconds. The "100%" takes an hour (and counting). Apparently $5K worth of cutting edge equipment is still not enough to overcome Adobe's programmers? What the hell is going on?

I can drag the exported file out of the destination folder kicking and screaming, and it appears to be whole (can play and upload to YT without issues). But until the encoding progress bar disappears, I cannot save the project or shutdown!