Earlier quoted context omitted.
Why are you calling it an unverified myth? In reality there are petabytes generated everyday proving the efficacy of mobile apps vs websites. This has been tested and measured in pretty much every possible way at this point with 100s of billions in ad spend. It's not just real estate on the screen, it's faster on-device processing with lower latency, rich offline abilities, better and more persistent access to more A…
https://de.wikipedia.org/wiki/Survivorship_Bias More often then not, the front end devs responsible for the app are not very good with "normal" web frontends - so they sabotage the competition, to reduce work. Also, web pages, could be repackaged into Apps by others leeching from the products attention.
Sabotage feels pointless given you're still competing against other native apps. Also I don't even know how you would 'sabotage' the competition, your average app engineer doesn't moonlight as a blackhat hacker.