You are correct, but on the other hand it doesn’t hurt to make the average person aware of alternatives.
Can be especially effective when the person buys a new PC and needs to do all the stuff you mention anyway. Yes, it is still a new OS, but honestly, it’s not that different - especially if the person remembers older Windows versions, it might just feel like going to familiar places (I know this is something my wife would really apreciate as she hates the constant changes of how things look). Obviously depends on distro, only have experience with Mint.
I’m saying this from a position of a resonably tech savvy, but not your average tech nerd (at least knowledge wise lol). Sure there are differences under hood but I don’t think the average user would really notice them that much.