If that had happened, I kinda feel like there would have been mixed reception about that.
Like, on the one hand, Armada Megatron becoming Galvatron after killing G1 Galvatron and stealing his power could have been interpreted as saying the Armada comics were incapable of having its own Megatron become Galvatron on his own from the power of something native to his own universe, instead needing to literally steal from G1 in order to do it.
And on another hand, Armada Megatron renaming himself "Galvatron" after having just stolen the power of the guy he just killed feels a bit odd when one considers that he would end up naming himself after a guy that he just proved himself to be better than. It'd be like, "I, Megatron, have now proven myself superior to Galvatron! So now I'll call myself 'Galvatron'!" What?!