It could be in the process of regularizing. There's no particular reason why "it's" can't be both things. Language changes.

One I've witnessed in my lifetime is "different than" vs. "different to". I was taught the first one. The latter sounds wrong to me, which is why I notice I'm hearing it more and more. (Note I have phrased this subjectively; I'm not saying it is wrong. I'm generally a descriptive grammarian. But it does sound wrong to me.) It may be a dialect thing, in which case my dialect seems to be shifting. Languages change.

The rule for possessive its is backwards from all other possessives. As a native English speaker, I still have to look up “its vs it’s” because it’s confusing. I think we should drop use of its without an apostrophe, and always use it’s, and let people figure it out by context. It’s happening anyway, and it’ll become de facto accepted English grammar when enough people use “it’s” differently than the old rule.

I've also learned to read contractions in their extracted form in order to help me when editing. It's a similar trick to remembering spelling versions of every word, like "Wed-nes-day", or "Col-o-nel". Sometimes I think it's more bothersome than it's worth. I could really use my own environment variables for `IGNORE_GRAMMAR` and `IGNORE_SPELLING`.

It never has, but it probably will now. Your comparison reminds me of the phrase "2.5 kids".

Also "Less" vs. "Fewer".