MIM parts are actually much more consistent in dimensions.

In the mass-production world, lots of hand-fitting means poor manufacturing tolerances, or prices you wouldn't pay.

That's no excuse for canted barrels, but more than a few stinkers left the factory pre-MIM & pre-1980.

Does it seem odd to anyone else that the quality problems began right when the internet became available to the masses?

As Billy Joel said "the good ol days weren't always great".