Kind of a shit move to suddenly pull the rug once they've finally gotten it working. Should have been kept out of main from the start.

The post clearly says the intention is to get a formal spec for formal integration.

To leave their experimental phase they have to define some goals to meet and that requires making some architectural choices that still aren't decided.

I suspect the recent "we updated the GC without a PEP and it went live and caused massive issues and we need an emergency point release revert" pushed for a greater degree of process overall.