On the other hand, if you consider the losses as a percentage based on people who gave up on the margin, you can easily derive losses relative to what they would have gotten without the bug in the tens of millions of dollars, and hundreds of millions is on the table.
I can't "prove" that, because the data isn't there, but it is a completely reasonable guess. At an 8 minute load time it is reasonable to guess there were a lot of people who stopped playing and thus stopped spending because they thought their install was crashed or corrupted, and just silently wandered away. I certainly wouldn't. I've got some games that load more slowly than others but I don't think I've waited multiple minutes since the Commodore 64 era.
Chiming in here as someone who used to play in competitive GTA leagues. I quit playing because of too much time spent in load screens. It was worse than just this slow loading bug: random disconnects that triggered loading again got more and more common over time, too.