Earlier quoted context omitted.
I don't know about being far advanced in the past, but we've certainly lost knowledge along the way. - Scientists still debate exactly how the pyramids were built. They have a pretty good idea, but don't know exactly. - More recently, we're not sure we could even recreate the engines that powered Apollo and took us to the moon. It appears that some of the critical knowledge was institutional, passed from one to the n…
That’s a silly argument, we could build pyramids 100 times bigger than the Egyptian ones if we wanted to today, and we can build engines that are far more efficient and powerful than the Apollo ones. Just because the specific methodology became obsolete doesn’t mean we lost anything along the way
The F-1 (the engine in the Saturn V, used in the Apollo missions) remains the most powerful rocket engine ever built. [0]
So no, we can't build them bigger, or even as well as, we used to.
[0] https://en.wikipedia.org/wiki/Comparison_of_orbital_rocket_e...