Not a rocket scientist either but I agree with your comment and expand on it further. It's worth noting that the Saturn V to this day remains the most powerful

Not a rocket scientist either but I agree with your comment and expand on it further. It's worth noting that the Saturn V to this day remains the most powerful launch vehicle ever created. So why didn't we just build that again? There are lots of reasons. Materials science has changed (ie there are newer, better materials now), the F5 engine was "handcrafted" in a way that required a lot of tuning and the whole system was expensive and unlikely to scale. There's probably lost expertise as a factor too.