Original author of the post here. I'm also a Blink API OWNER, so can happily report that Container Queries have 3 LGTMs and will ship in Chromium browsers very shortly, likely 105 (shipping to Stable in September):

https://chromestatus.com/feature/6525308435955712

Subgrid is progressing thanks to engineering from the Edge team, and I expect it to land this year.