Around 1990, my car didn't have power steering. Anyone who had a go driving it would moan about how hard it was. Many older jets had manual controls that were also more difficult to handle. Modern jets are so much assisted, that designers can choose the feedback forces.
G tolerance isn't all about fitness, some fat knackers are incredibly resistant to G. Practice and experience help a lot as well. If these super fit sports stars had a few goes, they would get it sorted pretty quickly.
My last aeroplane sortie in the RAF was back seat in the Reds Synchro Pair display. When they all dismounted together in front of the crowd, I stayed in the seat, trying to realign my gyros. The ground crew released me 5 mins later, I was a broken man.
Smiling from ear to ear