Hobbit on Quest
Yeah, it seems unlikely to be much of a toxic play style as much as one that someone particularly introverted is going to stick to because that's how they're comfortable playing. It seems to me that dishing out individual XPs based on active involvement is going to tend to discriminate based on player personality rather than a real difference in PC performance.With all the usual caveats about everyone's experience being different, etc., etc., I have a hard time seeing this being a real issue, since getting involved in what's going on is what makes the game fun, so there's already a motivation to do that. But the converse does seem like a big problem: giving individual characters XP for things they do runs a heavy risk of discriminating against support-oriented playstyles. You can try to parcel out each character's contribution to an outcome, but it's just about impossible to do that objectively (reminds me of the rich business owner who says they don't benefit from government, despite the fact that their business uses roads, employees educated with public money, scientific and tech advances developed by others, etc.). Better to just take as a given that everyone contributes, and not split hairs about who did what.
Of course, mileage may vary. A player might cynically exploit either XP generating option - but if so, that sounds more like a toxic player than a naturally manifesting toxic play style.