Even before the recent upsets, for technical reasons the vibe I had been getting is that for a long time now Unity has been tolerated, not celebrated, and this latest move has tipped the scales and made tolerance no longer possible for many.
There have been multiple ambitious projects aimed at finding a more efficient way to process game entities, and more efficient ways of rendering them, but that has only resulted in a fragmentation of the ecosystem.
Despite spending countless millions on trying to stay technically relevant, Unity has been living on past merits.