Input type 'number' also gives you weird step helper which most of the time is unnecessary and there isn't even a simple way to disable it.
Somehow HTML stopped innovating for so long, the latest revision (HTML5) is just mostly fixing what sucked with HTML4 and adding stuff other third parties already did better.
But i sadly agree, JS stuff is going to be needed for a long time.
The current datepickers on the desktop are "consistent in the same browser across many sites". There is no native solution for "consistent in the same site across browsers", which makes a lot of designers and PHBs upset, doesn't always fit the overall look of the site, and makes it harder for developers because each browser brings its own quirks with formatting, localization, validation, etc.