While the Resurgence folks were tough, they had the weakness of being vulnerable to taking out the leadership. The giant mommy would be child's play for the MCU if she started running around on the planet as in the movie. Also, I vaguely remember someone saying they were taking down the shields. Yeah, they could take out the planet from space but that's not usually done in the invasions postulated.
Of course, the normal MU has no problem with these folks but it's the MCU. Interesting to see how the Phoenix plays out. If Jean is up to the best comic levels, then all the invaders are toast.
BTW, if you teleport into a big ship, you can probably destroy it by messing with it's power plant or munitions stores. If you look at WWII hits on batteships, several are taking out by such one or few hit strikes. Folks wondered why the rather small nuke in ID4 destroyed the whole ship. My view was that it ignited one of those two energy sources. The Prince of Wales and the Hood - a good hit took them both down.