Possessive apostrophes are apostrophes (’) used with the letters at the end of a noun to show ownership over or a close connection with another noun. For example, if you were talking about the tail of your cat, you can add a possessive apostrophe and an s to show which noun is the owner.
The important thing to remember is don’t use possessive apostrophes with any pronouns, either possessive pronouns or possessive adjectives.
If you see an apostrophe with a pronoun, it must be part of a contraction.
its—possessive adjective of it
it’s—contraction for “it is”
The nature of the object doesn’t change which form to use (which should make it easier to determine which is correct), and the correct form is not a debate.
Sure, language changes, but for now that’s the accepted rule.
its*
(It’s is it is)
“Its knees work hard because it’s severely overweight.”
It’s*
noun, possessive
The cat has knees. It’s knees are powder.
From your own source:
“When should you not use a possessive apostrophe? Do not use possessive apostrophes with pronouns, which have their own unique possessive forms.”
You wouldn’t use he’s or she’s or they’s for possession. It goes: his, hers, theirs, its. The cat’s knees = its knees.
Here you go: It’s vs its https://www.grammarly.com/blog/commonly-confused-words/its-vs-its/
We both used links from the same source.
I’ve traditionally used no apostrophe for inanimate objects, like a bus.
But when dealing with a gendered, thinking being, use the apostrophe.
Edit: no need for down-votes for a good-faith discission, is there?
From the page that you linked:
The nature of the object doesn’t change which form to use (which should make it easier to determine which is correct), and the correct form is not a debate.
Sure, language changes, but for now that’s the accepted rule.