Earlier quoted context omitted.
Hard service to offer. The guy who originally built this and sold it to Google has posted on HN a few times about the intricacies of the industry.
Just did a little sleuthing and see that it was ITA[0] that Google acquired in 2010/11. Also I found this person on HN that looks like the guy you mentioned?[1] Lots of interesting comments for bedtime reading there. In any case, It's pretty clear that this is not some small insignificant service, which makes this somewhat blazé announcement of it's imminent shutdown (just find another service!) all the more infuriat…
There's other companies that will sell you the data, if you have a large pile of money (Sabre, Amadeus, etc.).
So it's problematic insofar as they're making it much harder for random small companies and hobbyists to get it. On the other hand, pre-acquisition this public API didn't exist. So it's not clear Google's acquisition of ITA made things worse in any way.
(Disclaimer: used to work for ITA. Have no inside knowledge of how things work now.)