Glock has already been doing this as an Agency only option since August 2022.Glock is supposedly going to be offering this soon, slides milled from the factory for whatever optic departments choose.
Also the Gunsite Glock pistol Holosun is a direct mount. The MOS1 I believe has Trijicon and some Holosun the MOS2 I believe is Leupold and Sig and the MOS 3 might be Aimpoint but can’t remember the order. either way it’s something along those lines.
S&W also is offering direct mounted slides. I would be more with using RDS if the direct mount was standard factory option (Yes I know companies mill slide but I don’t care. I want a factory option and no one will convince me so if yours works that’s great)