After updating to Build 22557.1 on 2/16/2022 the new style Task Manager showed up and worked as advertise in the blog except for a minor bug with the Title of the tabs defaulting to Processes regardless of the tab selected to open as default in settings.
A day later on 2/17/2022 the new Task Manager started to revert to the old style on some machines randomly.
Other machines still have the new style Task Manager.
It appears to be another typical A/B testing done by MS without any warning to the users.
On one machine it reverted back again on 2/18/2022 after I restored it to the new style the day before.
I have no problem participating in A/B testing, but I'd like MS to notify when they change those experimental features so that the users are not left guessing on what is happening.
This comment is in the Blog:
[We are beginning to roll this change out, so it isnβt available to all Insiders just yet as we plan to monitor feedback and see how it lands before pushing it out to everyone.]
FEEDBACK: Please file feedback in Feedback Hub (WIN + F) under Desktop Environment > Task Manager.