GPL3 was practically created to cover this case, as FSF lawyers didn’t feel that GPL2 is enough to enforce that. Check out the TiVoization clause in GPL3 and its history.
No it didn't. GPLv3 was created to cover the case of hardware vendors not allowing to run modified code. They still have to abide by the terms of the license even if they use GPLv2 -- that is, releasing the source code.
I thought GPLv3 was for many issues, not a single issue.
For example, the software-as-a-service loophole that GPLv3 (and AGPL) closes. We actually had an exploitation of said loophole for the open source Space Station 13 game. People were making changes to the game (each server runs their own modifications, and, the game is pure client/server so the entire 'game' is server-side binary only with dumb clients connecting) and some people were making important modifications and not sharing them with the community AND it was intentional because their mods made them the most popular server to play on (because nobody else had the features). It was a big stink, and eventually someone "leaked" the code, but then nobody could tell if that was legal to use or look at and it became a big, confusing legal grey area. All because they didn't start with AGPL or GPLv3 (or some other SaaS-aware license). The original authors probably didn't think anything of it and just thought "GPL is 'good'. So GPL it is." and that was the extent of it.
What you said is irrelevant to the discussed topic. With GPLv2, the hardware vendors must ship source code -- that is, follow the license. GPLv3 doesn't change this fact nor was it created to make this requirement, as it was already present in GPLv2, which is what we discussing.
