Is GTA 6 too violent for teenagers?

Probably yes. Grand Theft Auto games are built around adult themes, so GTA 6 is very likely to be too violent and mature for younger teenagers.

The series is known for violence, crime, strong language, drug use, and sexual content, and if GTA 6 follows the pattern of the earlier mainline games, it will likely be rated for adults rather than teens. The exact rating and content details can still change before release, so the official ESRB/PEGI listing is the best source once it’s published.

If you’re deciding for a teen, check the final rating and any parent guidance before buying, and consider using console parental controls if you want to block mature-rated games.