>internal development teams (who end up being stuck doing this kind of work)
I can just imagine your job ads now: "100% of your job is doing the work all developers hate to do!"
The reason I hate doing it as an internal dev is because nobody at the company really sees it or appreciates it and it is not part of my goals, it is usually well outside my stack and area (often a lot of time in the DB where I am usually not), and if you are any good at it, you get to be the new support guy for issues with it from now on.
Everything for the migration is also a one off hack so you are not writing good code, but good enough code.
At a prior job, doing well at a migration meant this one dev got stuck doing all the support work.
As a dedicated job, Hotswap would probably want to reuse scripts regularly, making it more like software development and less like console program hacking.
I would argue that anyone would accept unpaid volunteer work from the best minds in a given field. Starting from that assumption and working backwards is how I arrive at the original assertion.
The "almost" part is aimed primarily at regulatory limitations where volunteer work is forbidden by law.
Both parties must actively want the other's offerings for work to make sense. If they say they are not hiring, there's no point checking any further whether this may be the case.