You definitely can, and many do. But D&D is the lingua franca of this space. If you say you're casting Magic Missile, I know you're going to toss a few d4 on the table. Even if I'm brand new to your adventure, if you say you're a Level 15 Magician, I know you're a pretty righteous dude. No other system has the same level of familiarity across such a broad audience.
I think you're right though. No one with eyes on a big audience is going to want to tie their brand to a Wizards product after this decision. Shame.
I think you're right though. No one with eyes on a big audience is going to want to tie their brand to a Wizards product after this decision. Shame.