I don't mind them either - i use bootstrap myself. But , i can't help to feel that i use it because i've given up on thinking i could do something functionally useful in today's web with my own CSS. It's become boring, tedious work, because mobile changes everything, you just can't do visually challenging designs there.

Flash was overused as well - it was annoying. However, i believe that something being removed without having a better HTML equivalent is a bad sign of technological regression.