VP9 had more browser support than H.265, the codec it competed against. It was Apple's hamfisted attempt to hinder royalty free codecs for the web (among other web standards) that gave some users a bad battery experience. https://ngcodec.com/news/2017/10/21/why-we-are-supporting-vp...

That Google didn't force VP8 over H.264 is what led to the unfortunate situation with Firefox needing to ship a binary blob. I'm happy that Google stuck to its guns in the next round.