I think you're underestimating how subtle and ubiquitous modern autotuning is. The video here is an extreme example of a very broad category of effects. In reality, almost every professional recording you hear uses autotune in the same way that almost every professional photograph you see uses color correction. Most people don't notice it most of the time (despite most people believing they always notice it).

An alternative you've also heard extremely often is a singer recording the same line 100 times, then producers going through each word (or each syllable) to cherry-pick the sample where it was most on-pitch and blend them together.

Neither one of these represents the singer's real ability (whatever that even means), but both can be unnoticeable by 99.99% of the population when applied skillfully.