That feature might be usefull for some cases. But it is mostly used for regional pricing. You do not even need an account to buy stuff on itch, i highly doubt they will ever implement such a feature. If they were, then a dev could release one project for asia with one price and one project for other region with other price. Also it would be possible to discriminate against people based on their location. By not giving them your free game at all or giving them your paid game for much higher price.
Have a game that is a tad bigger . Go to steam. Have your geo blocking.
Delist your game. Only link to it on sites geoblocked from your unwanted audience.
Do not put language of unwanted area in game.
Have the download link point to a geoblocked hoster.
Do the reasonable thing and have a disclaimer stating the obvious, that it is fiction, characters are not minors and no celestial beings were harmed during the production. And that people offended or agitated by religous topics should not play it.