What so many people fail to realize about these issues vis-a-vis Google, it’s not so much the issues of Google having a monopoly or not on the ad market...in either case google is a dominant market incumbent that uses its position (in this case web traffic, data and online ad platform) to unfairly compete and stifle competition. Google has often used data acquired through their market position to start subsidiaries t…
Before Google Flights we were mostly competing against Expedia/Kayak/etc. Now Google Flights indirectly gives the airlines the top rank again, and we're competing against the OTA's for the secondary spots with ads and SEO. I can also anecdotally attest that Instagram ads work very well for airlines. (Well... worked very well, pre march 2020 and all).
I do agree with your main sentiment though, and the case could totally be made that google flights is doubly screwing over the OTA's now. Just wanted to share some interesting anecdata.