For AV1 this is true, but we don't really need to postulate about whether or not Apple plays games to suppress open codecs, they do it constantly. Like when they finally eventually added support for Opus, but not Ogg containers, so you had to stuff Opus in a CAF that only Safari can support. Opus is also now supported in WebM, but you still can't just decode Ogg Opus, and there is still no sensible audio-only Opus container supported in Safari right now.

Apple devices have had accelerated VP9 devices for literally years, which didn't stop them from simply not supporting VP9 during that time period, despite no reason (i.e. battery life) and despite that it has been patent unencumbered for that entire period.

And so much for battery life... If you are on a Wikimedia website on an iPad, it will use open codecs no matter what, and if you are on an Apple device, you might just get a software decoder in WebAssembly instead, if you're not on a new enough OS.