As for the encumbered media formats point, it's been mainly a Mozilla and Google thing, as both distribute their browsers gratis. Apple already pays lots of money for patents on other aspects of their devices, like the wireless connectivity parts. But Apple has been warming up to open formats slowly. They've implemented opus support in Safari (although sadly no ogg/opus). They've joined AOM and maybe one day they'll implement AV1 in Safari as well.
In general, there is a ton of momentum behind H.264 and its successors which is hard to direct towards open alternatives. Outside of browsers, media formats like VP9 are practically dead. Most video cameras use H264 or H265. DVB-S2 uses H264.
Apple's own way is to cripple it to force people to use the App Store. Google's and Mozilla's incentives at least mostly align with those who want an open web.
> As for the encumbered media formats point, it's been mainly a Mozilla and Google thing, as both distribute their browsers gratis.
No, an open web means anybody can contribute and consume without worrying about licensing gatekeepers. By pushing for encumbered formats in web standards, Apple explicitly took a stand against this idea.
> In general, there is a ton of momentum behind H.264 and its successors which is hard to direct towards open alternatives.
All the other browsers supported VP8/9. Apple stuck with H.264 and H.265 until licensing issues forced its hand.
> Most video cameras use H264 or H265. DVB-S2 uses H264.
Most videos created by people are on phones, which save them in the formats that their phones support. It was up to Apple to make its phones support an open format for use on the web, and it refused.
The rendering engine of Safari is similar to blink but not the same. And more importantly, Apple has the money to finance WebKit coming forward, as well as the willpower as they love to implement things themselves. I'm not so sure about how well Mozilla will do in the future compared to Apple.