No he didn't.
A bit after the dude who posted the video about EULA violation, Rockstart responded to the same question on the newswire, and said that their singleplayer modding policy is the exact same as the policy for GTA IV.
What DXG probably did wrong was accidentally go into online without deleting his mods.
Source : *LINK*
“I’m having soo much fun with GTAV on the PC but I just have one question about it, how come you are not allowing mods for it?” - @ClarkMatthew63
“Will I get banned from GTA Online for using a FoV Mod or Oculus Rift mod?” - @Mattophobia
We have always appreciated the creative efforts of the PC modding community and we still fondly remember the awesome zombie invasion mod and original GTA map mod for GTAIV PC among many other classics. To be clear, the modding policy in our license has not changed and is the same as for GTAIV. Recent updates to GTAV PC had an unintended effect of making unplayable certain single player modifications. This was not intentional, no one has been banned for using single player modifications, and you should not worry about being banned or being relegated to the cheater pool just for using single player PC mods. Our primary focus is on protecting GTA Online against modifications that could give players an unfair advantage, disrupt gameplay, or cause griefing. It also bears mentioning that because game mods are by definition unauthorized, they may be broken by technical updates, cause instability, or affect your game in other unforeseen ways.
This post was edited by razer11 (2015-07-24 10:33, ago)