Surprisingly, Rockstar have now added BattlEye anti-cheat to Grand Theft Auto V / GTA Online, and sadly it seems they have not enabled the support for Linux desktop and Steam Deck with Valve's Proton. ARTICLE UPDATED.
Same thing happened for the whole Bioshock series. They rolled out the update just over 2 weeks after a big sale so it was beyond the standard refund policy too.
Same thing happened for the whole Bioshock series. They rolled out the update just over 2 weeks after a big sale so it was beyond the standard refund policy too.