And what does it matter to you if people choose to play it solo? Are you afraid that suddenly everyone will do it that way? (Npcs are still slower and way more punishing than a good player run) And if somehow many play it that way, than these probably would not have done much group content anyway.
The solo part is a great way for more people to enjoy this game. I never started WoW years back because I did not like the thought of doing it with people I dont know. I hated having to do dungeons when I started FF14. And I was so glad when we got the NPCs. If we did not have these NPCs to run dungeons with us I simply would have done the story dungeons once and played more gathering and crafting. (Or found some people in other FCs that I know to run it with me)
So in the end you have two easy solutions: Go find a group yourself with the group finder and do it with them. Or find a active FC that will run these things with you. Having a static is often needed if you want to do the harder content.
And eventhough I prefer the solo playstyle I still found friends in this game. One I would even count as a best friend. He too is more of a solo player. Yet we both know enough other people which in turn know people or have big FC behind them that we could run stuff in groups. We do it for palace right now. We run it either as a duo or a trio. So if there is a will there is way.
