Buuut seeing it did get him interested to revisit some of the old Godzilla movies with me! He's almost certainly seen some in the past but when I was super-young so he didn't remember much besides the names of the major monsters.
So over the weekend I watched both Ghidorah the Three Headed Monster and Godzilla vs Mechagodzilla with him, curated to pick the ones with good human plots.
Best part? I managed to hide the title with Mechagodzilla, so the twist got him by surprise ^^
Both got thumbs up from him, with Mechagodzilla getting the small nod as his fav of the two.
For my rankings of G:KotM, I find I like the other recent Kaiju movies I've watched more (Pacific Rim Uprising, Rampage), but it is a lot more memorable than the first one. C+, out of kaiju movies. It's better than a number I can think of, but doesn't go in the upper ranks to me. Could go up or down with time- and I am looking forward to Godzilla vs Kong, so there's that.
Ghidorah and Mechagodzilla are A and A+ respectively, being two of the best Showa Godzillas ^^