As far as the ergonomics go, it STARTS here:
A high-thumb grip on a 1911 tends to lessen the pressure the web of your hand exerts on the grip safety. If the grip safety is not compressed far enough to disengage it, the gun won’t fire.
But wait. there's more. The beavertail grip safety prevents hammer bite, spreads the recoil load over a wider area, and kind of funnels the hand into a good grip on the draw. Fine. But that wasn't enough for the gunsmiths serving the run n gun market. They started shaping the beavertail higher and higher, to the point that the frame had to be extensively ground away to blend the contour. This permits an even higher hold on the gun, a slightly lower bore axis to reduce muzzle rise. But this opens up the palm hollow even more and puts the pressure on the grip safety near its pivot point, reducing the movement and force needed to disengage the safety. Hence cometh the "memory bump" to regain some of that contact. And actuating arms filed down for early release.
I loaned a new shooter a 1911oid (until she went Glock, so you can rub it in) and had to cement a hard rubber pad on the bump to give her enough contact. Another shooter here had the bump welded up into a hump for a permanent cure.
History: Many posts here and elsewhere said "John Browning didn't design the 1911 with a grip safety." Of course he did, otherwise it wouldn't be a 1911, it would be a 1902 or a G.R. The US Army requested a grip safety as of 1907 and all later Colt/Browning developmental models up until the actual 1911 had one. So did the Luger, so did the Savage. Why? It was in the mil-spec.
Mr Browning obviously did not have anything against grip safeties, he put them in numerous other pistols not going to the US Army.