It would be strange if all the greatest minds of human history had indeed merely muddle in the swamp while ignoring all those beautiful low hanging fruits. Even great scientists or mathematicians often produce absurdities when delving into philosophy. Either this is a task completely useless and difficult, or useful and difficult. But theoretical discoveries don't seem easy at all.

Optimistically, I believe there's a massive hindsight bias. But if this is true, philosophy is indeed a sad craft, gems continuously slip from our hands, while he are left with nothing but mud.

On the other hand, I must say sometimes I feel we are slow and stubborn independently of the difficult nature of the huge search space. Perhaps my comment bellow is evidence of that. I remember one time young-Nick said he convinced a big time philosopher of some point, I said "Well, that's it, you should erase everything on your CV and state just that. Forget your fancy PhD, convincing a philosopher triumphs all!". Old-Nick once told sometimes he felt philosophers where only reinstating some long held "truth" they had since early on, and they would build their publications, careers and life over it. How can one be so pathological stubborn?

The weird part is that even though is difficult, hard to advance, its few breakthroughs not acknowledged, relatively low paying, it still is the most competitive academic career, by far. I say all of this, yet I'm pulling all nighters since January to mildly increase my odds of getting in a good philosophy PhD. Maybe only an anthropological/psychiatric study to find out what hell it's wrong with it. I'm sorry if I'm inadvertently psychologising the question. I have been around our kind from birth and can't help but relying on personal experience.

Can't help also remembering the meme "It's a dirty job, but somebody's gotta do it". Is it some kind of necessary evil? Or maybe it is just an ol' boys' club - 2500 years old -, and we gotta show we are tough, stubborn, ruthless and hard to join. Wonder what Robin would say of that.

Finally, although this is no longer true for English speaking contemporary philosophy, might be worth noticing philosophy has also been chiefly a highly influential political activity. Due to its political influence, sometimes you would not be finding the truth, as in science, you would be setting things to be true. That would explain the stubbornness. You are not convincing people of the truth, you are convincing people of what they ought to do, sometimes even through legislation. Today we've lost this powerful role, but it would seem we've maintained the stubbornness. But, wouldn't MIRI "theoretical discoveries" have this moral flavour? You shouldn't expect people to easily buy all your claims, for if they unrestrictedly do, they might be bound to abandon their lives, move to Bay Area, and research FAI. You might be in the fruit selling business instead of fruit finding. They can low hang all they want, you've got to convince people into buying them.