If this weren't true, Apple could just start inserting ads into every iphone's Safari window tomorrow, and Youtube could serve the ad in the same stream as the video to defeat adblockers, and they'd make a bunch of extra money with no downside. The fact that they don't do this suggests that Apple and Google understand this: people only tolerate restricted platforms that do a convincing job of pretending to be unrestricted. In practice, this means that step 1 of Google foisting off user-hostile stuff on us is getting Firefox to include it too, which is presumably why they spend so much money on it.
