Dan Houser said he wanted to make more games in a certain time period and not focus on one big game every decade or so. Could it be that GTA 6 got him too realistic and he just wanted to create a classic GTA again?
Maybe he liked the chaos and the big weapon wheel with every weapon in our pocket. Maybe he was more the type of guy who wants to create games that you play after a hard day at work or so. We fanboys ofcourse also play a GTA that has a realism of RDR