I think back to the early days (circa 2000 or so), before CSS positioning and float hacks were even a thing, working as the lead webdev at Upromise, meticulously hand-crafting complex layouts with nested HTML tables... you could nest them 5 or 6 levels deep before running into noticeable render performance issues in what must have been, what, IE4 and NN4? It really has been a couple decades, hasn't it. Kinda wish every FE dev had to follow the path the industry took to get where we are now...
/ramble