Probably worded what I meant incorrectly. Like your example, since there was so much chatter going on, it doesn't mean it was non-feasible and not at least somewhere along the planning stage at UC when those insiders talked about it. We've heard lots of rumours here that didn't come to pass, I don't doubt their legitimacy at the time because they never came to be though.
So yes, while the rapid run of GoTG plans doesn't guarantee Disney is actually following through, it still leads me to believe the chatter at least makes it very feasible - or Disney at least thinks it is or wants it to be.
The article was great by the way, but I still really don't see how GoTG is precluded or really covered by the language anywhere. The main argument seems to be GoTG appearing in the MCU (which isn't what the contract even covers) retroactively brings them into the Avengers family. That seems silly to me. It would be like Marvel doing a weird future comic book run where they pulled characters out of the Star Wars Universe and introduced them into the Avengers (stranger things have happened in comic books). In no way would Disney retroactively lose the Star Wars rights to Universal as a result.
I don't think it's about retroactively bringing GOTG into the Avengers when they were already featured in the comics with them before the contract was written.