To be clear, the goal of the FSF in creating the GPL was to protect the end user freedom by encouraging use of a libre boilerplate license. The GPL is not a thing which can have a goal. This distinction matters, as the goals of the license authors may not perfectly align with the goals of the project authors choosing to use a license.
In the case of Linux, the goal in using the GPL2 is to get competitors who don’t trust each other to collaborate on a project. The LF, and Torvalds, would prefer the drivers for some bit of hardware provided to the kernel, but the hardware device require signed kernel images, rather than have the hardware vendor use the BSD kernel. In neither case can the end user run unsigned kernel images. In the former case, someone can at least audit the kernel source to know what it is doing, or could even make a clone of the device without the signed firmware requirement.
As for trying to get around licenses… note that if you allow but don’t require a recipient to re-license under a newer version, a nefarious recipient will choose whichever license best allows them to abuse the system. This means if they receive a GPL2+ source, and wish to TIVO it, they’ll just take it under the terms of the GPL2, and pass it along under the terms of the GPL2+. If you want to later force them to use 3+, you must still relicense the project, complete with rescinding old licenses where applicable.