While horses would be awesome, they wont be ridable. They will be used at the horse racing track.
Is that fact or just your opinion?
Well they could just edit in a bit of the RDR code to get rideable horses/mounts into GTA ...
exactly. people forgot rockstar made the most kickkeister western and zombie western imaginable and marston was able to be chosen as part of your family.
Because a large, western world with no urban elements or vehicles is a lot easier to determine collision issues, gameplay mechanics, etc, than it would be if you threw cars, buildings, and all that in.
It's not a matter of copy and pasting code, especially when Rockstar North had next to no involvement in RDR.
"lol der was a shdow on my carpet but ti looked like a stane and tried to clen it up but ti was a shadoow" -Ghost4800