The first two sentences of the paragraph:
Those attitudes are the ones discussed in the previous paragraph. They were attitudes about ideas dying in your place and focusing on correcting errors I think. Those are accomplishing the goal of pushing back against mainstream views about mistakes.
That mainstream hostility to mistakes is the stuff about being weak and bad for admitting to mistakes. They’re hostile about making mistakes. That hostility is irrational and anti-fallibilist. If it was some other kind of hostility then it wouldn’t be subject of this article I think. That hostility makes it seem that we have to be right in order to be strong and good in society. It’s like making mistakes is really bad for you and it makes one think that making no mistakes is the goal. It’s like making no mistakes is the expectation to life.
This is saying that the attitudes have a shortcoming. The attitudes don’t say what to do with the mistakes. They don’t talk about doing something practical with them. Like, yes it’s good to not be so hostile about mistakes but what about dealing with them? The attitudes aren’t sufficient enough to encourage using current knowledge about a problem.