If you look up gta vi free download, the verified details show the game is a paid release

https://shaneariw721.capitaljays.com/posts/gta-vi-for-free-co-oznacza-oficjalna-strona-pobran-gta-vi

If you look up gta vi free download, the verified details show the game is a paid release, while only promotional assets like wallpapers and trailers are available for free.