ELI5: Why are so many document editors - Word, Google Docs, etc. - so notoriously counterintuitive when trying to adjust formatting?

Why do they all do this?

Want to move a table by grabbing it and moving it? Okay, we've added page numbers and deleted the headers instead.

Want to press tab to indent a line? Okay, this time we've decided that means all the lines. No, just this one time.

They're so user-unfriendly for anything besides typing up an essay or something I'm left to believe there's some back-end reason that this is the more salubrious code.