Definitely did not take me that long to read, though I skimmed pretty quick as I know most of this stuff already (unlike the js stuff you were posting about before). Float still gets my hackles up, I have had so many problems with it I basically avoid it like the plague now XD
Love flexbox though, one of your best friends for responsive layouts :D
I feel the same way, once I was learning about Float I was like "damn, this is too complicated for a freaking layout, no wonder why people stick to wordpress" but then during Flexbox I was like "Ok, looking better, this is intuitive and simple once you get the logic", and then with Grid I was like "I could do this half drunk, I love it" hahaha.
Wordpress themes use all this nonsense too XD
Yeah but in a kind of easier way doesn't it? Kind of clicks and sets, not code and sadness :P
I guess? Admittedly the only time I've ever looked at Wordpress was from a coding point of view (was thinking of doing themes for it) and at the time (a very long time ago now) it was pretty nightmare x_x