Incentivizing group play by limiting solo play seems like a very archaic approach to game design. And with a smaller game population it's just plain silly. From what I've seen if people have a group available to play with they're going to choose to play with a group over any minmax efficiency solo.
In Path of Exile the largest reason people don't play in groups is optimization, the game cooks even good computers with all of the stuff that flies around in that game. And for the hardest bosses, most people fight them solo because the health multiplier is very steep when the bosses have billions of hp. And again, it's really difficult to fight bosses with all of the crap that flies around.
But even with these massive drawbacks to group play, people still play in groups when available because 1. It's safer. There are a lot of mechanics that different party members can utilize to buff each/others. This is especially prevalent in the hardcore leagues. And 2. Many people find it more fun. Whenever a solo player is asked why they don't play in parties they always give the same two reasons "Solo self found" or, significantly more commonly and less memey, "It's too laggy." But even the most stubborn of solo players will admit that if they had someone who was willing to be a dedicated support who was always available to play with when they were playing, they would definitely play with them.
It's also worth noting that there is a small subculture in the PoE community of a "solo self found(SSF)" style of gameplay, but it is largely in response to how many players feel that trading is too cumbersome. PoE also has a large presence of "competitive ARPG" players who feel that group play is too easy and a smaller subset of that population feels the need to prove their ARPG prowess by playing SSF.
I can't imagine there being any significant drawbacks to allowing solo players to play everything that multimode players can. I strongly doubt that there are >5 players who would choose solo play over group play when both choices have equal access. If anything, it would increase the overall playtime on the server and potentially increase the likelihood of groups forming as there would be more people on the server playing for longer periods of time since they no longer have to sit around waiting for their group members.
In Path of Exile the largest reason people don't play in groups is optimization, the game cooks even good computers with all of the stuff that flies around in that game. And for the hardest bosses, most people fight them solo because the health multiplier is very steep when the bosses have billions of hp. And again, it's really difficult to fight bosses with all of the crap that flies around.
But even with these massive drawbacks to group play, people still play in groups when available because 1. It's safer. There are a lot of mechanics that different party members can utilize to buff each/others. This is especially prevalent in the hardcore leagues. And 2. Many people find it more fun. Whenever a solo player is asked why they don't play in parties they always give the same two reasons "Solo self found" or, significantly more commonly and less memey, "It's too laggy." But even the most stubborn of solo players will admit that if they had someone who was willing to be a dedicated support who was always available to play with when they were playing, they would definitely play with them.
It's also worth noting that there is a small subculture in the PoE community of a "solo self found(SSF)" style of gameplay, but it is largely in response to how many players feel that trading is too cumbersome. PoE also has a large presence of "competitive ARPG" players who feel that group play is too easy and a smaller subset of that population feels the need to prove their ARPG prowess by playing SSF.
I can't imagine there being any significant drawbacks to allowing solo players to play everything that multimode players can. I strongly doubt that there are >5 players who would choose solo play over group play when both choices have equal access. If anything, it would increase the overall playtime on the server and potentially increase the likelihood of groups forming as there would be more people on the server playing for longer periods of time since they no longer have to sit around waiting for their group members.