Nothing prevents a vendor from implementing a high quality hardware encoder, just as nothing prevents the creation of a low quality software encoder.

Video editing is an area that Apple dominates because PCs become a laggy mess on complicated high resolution edits.

AMD has started to copy the same strategy with the recent Ryzen AI chips. They include hardware video encode/decode units as well as unified memory.

> Nothing prevents a vendor from implementing a high quality hardware encoder

Uh yes, it's called reality. Advanced video coding techniques are just too complex, full of serial and branch heavy algos to work in decently sized and priced ASIC or even in GPGPU. Which is the reason none exists outside of very expensive special stuff for professional render/streaming farms.

Not even mentioning that few coding tools are shared between codecs, so while you only need 1 CPU to handle all of them, you'd need almost an ASIC per codec...