Who cares about hardware you can't utilize? Its just a piece of silicon with potentially any performance imaginable. What you can do with it, now, matters. If this changes in some theoretical future, well we re-evaluate performance claims and stats.

Nobody bothers to guess what's the potential of some new graphic card once all drivers, games, OS etc are fully tweaked and optimized. You decide on performance now.

You can already use it now if you're targeting the platform. It's not the platform provider's problem if you're using a compatibility layer, that was your choice. Well, from a development POV at least, from a user POV, if your tools are using the compatibility layer, there is not much you can do.

We knew this would happen for everything using Rosetta, that's just part of transitioning to a new CPU architecture. For Vulkan vs Metal that's self-inflicted on Apple's part.

You mean that we should take into account how actually complicated is to get software that fully support the hardware into account for HW comparisons where a type of HW can only run with a specific OS?

No, I mean that's not relevant to compare what the hardware can do. It's like how the PS3 was super hard to program but in the end it was producing more impressive results than the Xbox360. This was not a surprising result, it was to be expected from the hardware. It's not that different from what is happening here, benchmarks running on x86 emulation on engines running compatibility layers for Metal are not representative of the hardware.

With the difference that Apple HW performance might be "good enough" for 3rd party software vendors if they take into account the extra development burden for the platform. Anyway some of those benchmarks were already using Metal and are still behind.