I'm convinced, SRAM, mostly SRAM is on notice. A T-Type GX AXS group alone, without crank and pedals is $1000+. Up close, I look their T-type transmission and can see the expense that a derailleur has evolved into: all the electronics, stepping motors, clutches, gear clusters, controls, micro shiting, etc. It's an apex derailleur and it's not even their top line, and to tell the truth there really is nowhere left to go with this, other than to pare it down. It didn't have to this way, but that's where the margins are chased - in the realm of higher-end ebikes.
An ECVT is just a bit more complicated than the motor already on your ebike - add one more smaller motor and open up the step-down planetary gear that's already there. So on net, you EMTB just got a lot less complex and a lot cheaper to manufacture. Even if don't jack up your bougie derailleur system every 500 miles, there's no way Gabao or Avinox is going to charge a grand more for their motors that end up on the new slate of bikes. The value prop is there at the get go, without adding replacement reserves.