You just need to look forward a few weeks to see a big one. The FaceBook and Instagram oEmbed changes that are going into effect at the end of October[1] are going to break all of the Facebook and Instagram embeds on WordPress sites (~1/3 of the internet) and the oEmbed functionality won't be available without a developer account[2].

[1] https://developers.facebook.com/docs/plugins/oembed-legacy

[2] https://core.trac.wordpress.org/ticket/50861