I suppose the one side-effect of giving GTA V away for free, other than crashing Epic's servers, is that there's a lot of cheaters out there who have either got a second chance at life or feel they haven't got much to lose - and as such, cheating in the game has surged over the past week.
I suppose this was to be expected, given the above. Still, many gamers have been stating the game is currently unplayable due to the level of cheating going on, in addition to the strain that GTA's servers are under generally due to the massive influx of players.
Not all cheaters are evil; many simply use their ability to play with the game to spawn interesting things or cause some harmless havoc, nonetheless, the cheating has caused legitimate players to become severely frustrated with the situation.
Because GTA V itself is so open to modding, GTA Online is easily broken, and cheating is rife at the best of times - Rockstar does try to crack down on cheating and have issued permabans. Still, the problem is largely out of control when compared to more competitive games.
I can only assume Rockstar will eventually get around to banning this massive influx of bad actors, but for now, GTA Online might be one place to avoid.