That is true. It would be very hard to include direct support for every piece of hardware on the market. Maybe compatibility for Linux or Windows drivers would be a good inclusion. But only time will tell.
The good thing about a lot of hardware these days is how it is all quite standardised. Most graphics and sound cards have built in support for generic drivers, so even if you can get the most from a piece of hardware, at least it will work. And most USB devices are quite standard these days, showing up as external drives to access their contents.
Things like printers and scanners are obviously more specific to each make, but again general TWAIN level support for scanners, and generic print drivers for each make do work with most makes and models.
There are normally ways around the requirement for specific drivers being needed. But obviously these will never be able to give the user the full feature set of the hardware connected.
Regardless, AROS is a really interesting and cool project that I am following closely. I even have a spare PC sitting here that I might install AROS on.