like obviously they don't go into detail about it but like. c'mon. their interactions. The desire to make up after the (pretty ideologically serious and legitimate, ngl) argument and Megatron making the first move to do so iirc. Megatron at Optimus' side WITHOUT Soundwave.

Originally I thought that the entire "Megatron is good now actually" premise was just Megatron putting on a front like he does, but while I still suspect he's going to turn and become a villain again, this episode really makes it feel like he truly changed sides, even if the question of whether he'll change them again remains open. Like, if he was faking I feel like Megatron wouldn't have taken it as easy on the cassettes, he would just have been "grr no I am Definitely An Autobot Now so These Are Bad" to sell his cover. idk how much thought the showrunners put into it but that's my theory for now anyway

And like, I repeat, you see Megatron on the opposite side from Soundwave, who I generally consider to be the most "ok whatever sure, if Megatron says so" Decepticon, so much so that if there were a non-robodick reason for Megatron to turn, I think Soundwave could've been convinced though maybe not happy to go along with it. But Soundwave called Megatron a traitor!?!?

I mean you do (finally) see Starscream in the G.H.O.S.T. prison and it's not clear whether Soundwave's schemes are for his benefit or for his own, but neither of those are particularly in character for him since Soundwave has historically never had patience for Starscream's shenanigans. ergo, Megatron turned for a reason Soundwave cannot relate to, ergo the pipe must truly be Prime!!!!