Strangely under-reported is that the same hacker is offering up to 100k to others who perform similar acts of hacktivism: https://www.vice.com/en_us/article/vb5agy/phineas-fisher-off...
So this activist has somehow profited from his “hacktivism” and he wants to spread his wealth to other activists?
The funds didn't necessarily come from the hacktivism.
Edit: Given the bounty is paid in bitcoin, somewhat more likely the funds are donations/fees from hacking. Not likely it came from funds deposited to an exchange (traceable account). Could also be someone who was mining in 2009 (and not from the hacking itself).