I think running a team cost money for most game devs so it could be an issue, also this is a big update like he said so it would take longer, and honestly if a team where to come in this already great game it could ruin the game as he was the one who most likely wrote edited and drew everything for the game so its an opinion of mine but the chose is up to the creator of the game.
A good team can definitely make things go quicker, but it can also cause progress to slow down massively, if you have even one person, who is not on the same page as the others. And that's also ignoring the costs of hiring others.
So right now, I find it far easier working on this game alone. Generally, I can get updates out far quicker than a lot of other devs I see on here, which have uploading schedules of 6+ months, sometimes even years.
And I was originally trying to do a release every 3 months, but from here on out, I think updates are going to be a bit bigger, especially when I get into act 3, so it'll probably be around the 4 months mark, in between each update.