And things are slow as we waste all that processing power on running javascript one way or another. And everything requires a slow blocking connection to the mainframe. Nowadays the “always connected” mindset is really slowing us down.
However there is definitely still less intrinsic optimisation from a dev perspective I think - people will iterate over the same array multiple times in different places rather than do it once.
I guess our industry has decided moving faster is better than running faster for a lot of stuff.