You don't need vendor specific tools. Especially not on the pi 4 but even before that. The RPi foundation stayed on a 32 bit distro with the proprietary graphic

You don't need vendor specific tools. Especially not on the pi 4 but even before that. The RPi foundation stayed on a 32 bit distro with the proprietary graphics stack forever due to some silly fear of breaking.. something (?) or whatever but mainline linux has been able to manage everything about graphics and display with the vc4 drm/kms driver for ages. CPU frequency has of course been controlled by a mainline kernel driver for ages – heck that's supported in all of the BSD OSes as well.