It’s just a cultural fit issue. Different people have different personalities / preferences, and what may be one person’s “red flag” may be the other person’s preference.
I've seen multiple posts by the author of this piece and I wouldn't want to work with that person. I've worked with people who have similar personalities, and it's just not worth it. You can find competent people who are easier to get along with.
John Hancock didn't sign "Concerned Former British Citizen"
Not the parent, not having a strong opinion on the author, but have felt similar about some people in the past. "Difficult to work with" is an issue, and I too prefer to avoid people that sort into that category. They'd have to be actually brilliant to make up for it, just being really, really good doesn't cut it.
Why? Because they add friction to things, and they poison the team's ability to get work done. Difficult people are not fun to work with, so everyone avoids them. And then they avoid using things the difficult person built because using it would mean you'd have to work with them if you run into issues, or want to improve it etc.
It's just much easier to find people that are easy to work with, and working with them is much more enjoyable. Even if they were not as good, my personal experience is that replacing one difficult person with two others is well worth it. A happy team is way more productive and makes up for it easily, so accepting someone that's difficult to work with is generally "not worth it" to me.