A few things - this is one step in a long, LONG path. AV2 is currently unusable in its current state (the encoder typically runs at around 1fps on good hardware), and likely will remain so til ~2028 when the first av2 hardware accelerated chips start dropping. Even then, I wouldn't expect AV2 streams to be common til 2030.

IMO, if it were just the efficiency gains on the table (which are substantial - ~20-30% over AV1), I'd say that AV2 isn't worth it. The biggest thing it does add though is multi-stream support, which will be a big win for VR and live sports. The other fun thing is you can send an alpha channel as a separate stream, which the file will then composite for proper transparent video support.