@goatsarah @thomasfuchs landing rockets was hard, but even there it had been previously tested out in the DC-X program.
Just nobody cared enough to try to scale it up before SpaceX.
Launchpad design had been done wrong before, and the lessons learned were incorporated into heavy launch facilities in the US, Europe, and even Russia.
SpaceX got overconfident and built a pad that wasn't fit for purpose and that they should have known wasn't fit for purpose.
Period.
That wasn't "oooh, let's try something new!"
It was "let's cheap out on stuff while the regulators have their backs turned"