Maybe "Bad Programmer" is more apt instead of "Hermit programmer" and yeah it is a no brainer that they are "dead"
Some of the very best programmers I've ever met tick all those boxes. They could deliver in a week something other teams would struggle with for months. The problem of course came when other people would try to understand and build on what they had done.
If you believe the quote that "Real Developers ship" then they where absolutely Real Developers.
Because of that I suppose I don't fall into this mythical group of programmers that can crank out something in a week that teams struggle with for months. I've done it several times but it's not how I usually roll, plus teams can be super slow sometimes so single guy beating them isn't a huge achievement. I've gotten a lot of accolades because I've "left the garden better for the next guy", several times.
They'll have to bring the base down to their level to understand and iterate on it.
If you brought another "hermit" in, he'd obsess over it and either refactor it in his vision or understand it and know how to flex it to continue iterating.
You bring a team of normal people in, they'll think it's too "adhoc", and rewrite it in a bloated and complex way.
Sure, but shipping untested, undocumented code in 3 days that is bug free, fast, rock solid and does everything it's supposed to do on the first try, takes a certain sort of talent. They might make very annoying colleagues, and the people who have to follow them might curse their names, but they're not "bad programmers".