Maybe not, but perhaps the mindset was different then. Besides which, I'd say that if it's an obviously intentional difference, or differences, such the the progression through four types, of the F164, 164A, 165 and 166, then they are distinct types, albeit the differences are slight, but nonetheless recognisable. This surely lends importance. If Peck had discovered and published details of the 164A in 1958, I'd lay odds there's be a lot more around than there currently are.
Same with mules where there are obviously incompatible reverse/obverse pairings. There have been enough minted for us to know that the minting was intentional, whether due to a broken obverse/reverse die necessitating the temporary substitution of an out of date die, or other reason.
Same again with overstrikes whether intentional as a result of "good housekeeping", or arising from operator error. They are all distinct types which have gained popularity over the decades.
Where it starts to get flaky is with tiny unintended differences such as sloping final ones on the 1861 or the far 4 on an 1864 crosslet. Quite a lot of these minor variations around - of interest, but not so much as to warrant separately trying to categorise them.