I would describe it as exactly "resolving a license compatibility issue". Taint in linux kernel refers to marking this kernel as not supported, which often just means not purely GPLv2 compatible anymore. Proprietary AMD and nVidia drivers also cause taints. https://unix.stackexchange.com/a/118117/251582

Yeah, the person you're responding to is taking "taint" to mean a literal ban situation; versus the very real status that exists in Linux Kernel development.

"TAINTing" a driver/code doesn't mean it's blacklisted, it means it can't be upstreamed into the GPL codebase. It means that if you build a Kernel with it, it's no longer considered OSS-friendly.

There are plenty of legitimate and viable codebases that use TAINTed kernels. The DoD, various government entities around the world, some commercial interests, etc.