Citizens of Mathematics-Land carry the Rapier of Proof at all times, and citizens of Physics-Land carry the Six-Shooter of Experiment, and anyone committing an offense or faux-pas meets swift and merciless punishment from his peers. Philosophy-Land is a weapon-free country, whose citizens can be rude to each other without risk.

In Medicine-Land and Engineering-Land, great material rewards befall those whose ideas are new and true, whereas those who cheat or deceive themselves may cause catastrophes. But in Philosophy-Land, there is no reward for honesty or hard work.

And how can philosophy do something about its level of internal disagreement without having to apply the "kick out everyone who disagrees with Less Wrong" solution?

I wouldn't expect progress in the field as a whole, I'd expect small subfields, departments, individual philosophers to try to solve those problems locally. And I don't know enough about academic philosophy to tell whether that's already the case; Experimental Philosophy may be a step in that direction. Maybe analytical philosophy was. Maybe the institutional incentives are such that any effort in the "right direction" tends to fail.