It's a demo bro. It's not false advertising he just hasn't finished the game yet.
he could've not put the fake prestige upgrades in the game or the fake screenshots on the page. in fact, not doing that was the default choice, and an active decision was made to put the false information up. it's 100% false advertising, because the game does not exist and neither does any of the content indicated, yet it still pretends that that content does exist