Pls, check price in the Russian region.
It's a huge difference with the Steam price.
Maybe it's a mistake.
It's not a mistake. Some genital wart of a person was abusing the GOG regional pricing to buy up copies of Factorio at RU pricing, and selling the generated retail keys Factorio devs use for upgrading the account at regular US price. Which led to the devs equalizing our region's price with the rest of the world.
Thankfully the Steam version is unaffected. I recommend getting the game there if you're in Russia.