Moreover, I believe he had a really bad time there because the population in the base was mostly military and they treated him like shit in the most military bootcamp style with physical aggressions and such. So, he ended up not completing the whole term. (This probably will depend on the country of course).
(Source: I am an Oxford resident.)
They could be from a country with a lost CoL so $28k is a huge deal, they could be living the life they want doing a job they love, etc... Just so happens some future tech is interesting enough that they wish they could afford that too. Not everyone is in tech for the FAANG bucks!
Although if GP wishes they could earn more I assume any account holder on HN is technical enough to find a remote job paying more than that if they wanted.
Full self driving would complete change everything. I could look at jobs I've never even thought about, because of the need for transportation.
You want to be a janitor or a deputy Vice Provost or something to work at a college.
£25k is definitely low though.