He was talking about out of the box functionality of linux vs windows.

Of course you can build SOEs with manually assembled sideloaded drivers, especially if your organization uses just a handful of different models.

At the enterprise level it is quite common, specially since they want to have control over every little piece of software that goes into the stack, including updates.

I even worked at a few places that created their own UNIX flavors (mostly GNU/Linux based).

They get the drivers from the OEMs.

They are also paid teams to put the image together.