Only the GPLv3 would force Intel to do that. With v2 they can go the TiVo route and make the source available without giving out the means to make the hardware run your own binaries.
If even one component is v2 rather than "v2 or later", then (I'd assume) the whole project is v2-only, majority or no. It's also not clear if it's permissible to make contributions under "v2 or later" licensing terms, since those contributions are derivative works of Linux itself (which is v2-only).
This will almost certainly always be the case, since changing Linux's license to "GPLv2 or later" (let alone GPLv3) would require unanimous consent from every contributor (and seeing as how - IIRC - one or more said contributors are dead, that consent is thus impossible to achieve unanimously).
And convincing Linus the rewritten versions are objectively better than the old ones.