It's probably never gonna happen and it's been beaten to death but R* has put out some good games with good stories just begging to be adapted into a TV show or a movie. Is it necessary? No but here's what I could see working
Max Payne - Yeah there was that Max Payne movie a couple years ago I never watched it and I heard it was pretty bad but Hollywood loves remakes. Should they try to make a Max Payne movie again? Maybe we get a movie trilogy covering the three games and Max's journey or maybe as a Netflix show?
Red Dead- I can see it working as a TV show like Deadwood or they make a movie out of John Marston's and Red's stories.
GTA- The only way I see GTA working is as a TV show. They have more time to develop the characters and story arcs over the course of a season. They can even switch between the time periods like what Fargo and Underbelly have done and share characters.One season could be set in the present day and the next could be set in the past.
Manhunt- Could work as a very gritty miniseries the plot with James Earl Cash could defintely work.
Body Harvest- That game came out when they were still DMA design but I think the plot is good for a movie or again a TV show might work.
Yeah it's probably not needed as we can enjoy the games a lot more than we ever would with a TV show or a movie but we can always imagine.