Safari was also late to implement AV1 video support. Based on caniuse website, only MS Edge was later, though you could install an extension to get it running.
Oh, and when I say "support", I mean you'd have to buy a new device.
Supported only on devices with hardware decoder, e.g. iPhone 15 Pro, M3 MacBook Pro, etc.
Edit: Chrome since v. 70 (2018-10-16), Firefox fully since v. 67 (2019-05-21), Firefox partially since v. 55 (2017-08-08) whatever "Not supported by default, but can be enabled" means, Safari since v. 17 on newer devices (2023-09-26)