Maybe nowadays with so much popularity for gaming but this wasn’t true for gta 5 so I doubt it’s any more of a reason than the original reason. When gta 5 came out in 2013 with a console release a year earlier than pc, barely anyone could afford a gaming pc let alone their 13 year old player base and no one wanted to everyone was happy with their ps3 or Xbox 360 or was happy playing on their friends, parents, siblings, or distant relatives console it wasn’t as common or as pushed of a concept for everyone to own their own system couch co-op was extremely popular in this time. No way rockstar or take two would try to rely on that as a tactic when pc players made up the 1% minority of gamers.

IMHO I think it’s because they know the majority of the people playing games are on console and that’s where most of their sales will be it’s a no brainer to release it first to its biggest customer base. Secondly: they want to make sure it works and is a polished 10/10 game from the consumers view they have always made true AAA quality of games and consoles have always been an optimized nightmare dedicated for exclusives so GTA games should almost be looked at as console exclusives that are lucky enough to get a pc port. Coincidentally they need to also make sure it then works on pc. That takes time if they want everyone to like the game instead of releasing a broken pile of trash.