I'm not sure why it matters if shady companies are slightly incentivized more to be shady?
If they don't really care, they're going to put the minimum possible effort on a separate 64 bit version too and it'll be just as inefficient anyways, except with no backwards compatibility.
By cutting off 32-bit support, Apple gets more people to buy a new computer, as new software versions are only available on 64-bit computers. It also removes the incentive for software vendors to keep producing 32-bit software versions.
If they don't really care, they're going to put the minimum possible effort on a separate 64 bit version too and it'll be just as inefficient anyways, except with no backwards compatibility.