Is "Revert to Legacy" really going to be disabled in Looker 21.18?

[Teresa_Kovich]

It feels like there are still a LOT of issues for which the Support answer is “revert to legacy, edit, and re-upgrade” (or for which there is no Support answer, e.g. the issues with funnel viz). Getting increasingly anxious as 21.18 grows closer:
 

Can the Looker teams (Product? DCL?) weigh in on whether there is any talk of pushing back the deprecation of this feature?

I’d love to have the community share examples of bugs for which Support’s recommendation is “revert to legacy to fix”, so that we can get a sense of the scope here.