It's hard to say, but imma say no. The Switch 1 was already capable of handling GTA 5 since it was on the Xbox 360 but Rockstar never brought it over even after bringing other ports like GTA Trilogy and Red Dead to Switch.
However, there was a valid argument that argues that Rockstar may have not wanted to support the Switch version of the game for updates since it was using the 7th gen version which would've been too difficult and costly to have to update the Switch version of the game specifically since it was too different from the PS4/XboxOne versions.
I have a feeling it won't come to Switch 2 mainly because I felt like if a GTA 5 port was coming to the Switch, it would've happened by now but it hasn't. Maybe porting over the PS4 version of GTA 5 may make it easier for Rockstar to port it to Switch 2 but I also have a feeling that Rockstar at that point will be too focused on GTA 6 updates to care much about GTA 5 anymore to port it to Switch 2. So i'm gonna say its not gonna happen.
I won't say it's impossible tho, Rockstar did quite randomly brought a port of Red Dead 1 to Switch and other games like GTA Trilogy & LA Noire. So Rockstar may look at porting to Switch 2 as sort of a legacy console to resell older games towards a new demographic and a platform that encourages people to double dip on older games to play them on the go for the first time. So it is still possible, I'll just guess that it won't happen