It is indeed [0], but there's about 14% of the browser world who can't benefit from it yet [1].
[0] https://developer.mozilla.org/en-US/docs/Web/HTML/Global_att...
[0] https://developer.mozilla.org/en-US/docs/Web/HTML/Global_att...
Also.. not sure what safari/iOS did in their early years with keyboard password entry capitalization... but if they did auto capitalize... since Apple is so good at saving profile info across new installs/os updates... I imagine there would be a large portion of old apple users with perma-capitalized passwords out there as well.