Technology has helped it and all other cartridges too.
Not nearly as much as other cartridges, due to Winchester's twist rate failure. The only good new .277 bullets are for other .277 cartridges that didn't make the same mistake.
The .270 has benefited from the development of slower powders, but again not as much as other cartridges because it's sized for the "fast magnum" (4350) and "regular magnum" (4831) burn rates, while superior competitors can make good use of the slow magnum (H1000) burn rate powders. That's unfortunate for .270 shooters, but I guess the cartridge designers can't be blamed for that one since those powders didn't really exist then. It's still a reason to move to a superior newer cartridge.
