One thin that people miss for dropdowns is that you can actually type N..E..W.. and it will select New Zealand. Most browsers implement some sort of combo counter for it, such that the entry resets after a while too.
I do agree that search boxes are better in general, and especially so for things that are not standardised such as country or airport 3-letter codes. But it's not the end of the world, even for date inputs you can just type 1984 and it'll select it for you.
EDIT: It does not change the fact that mobile dropdown implementations are horrendous.
It's why I always recommend against non-native controls by default, whether on the web or desktop/mobile - even if you're particularly observant about your platform (and most devs aren't), there's probably still a bunch of little things like these that you'll miss and won't implement, and that people actually use daily.
And not only that, but unless you're observant about literally every platform on which your app will run, you are bound to break something, whether subtly or majorly.
I thought it wasn't working, but apparently on FF you have to do it really fast. Take a second between key presses and it'll just revert to the old behaviour. Talk about being shitty to people with poorer motor control or who need to hunt and peck.
I do agree that search boxes are better in general, and especially so for things that are not standardised such as country or airport 3-letter codes. But it's not the end of the world, even for date inputs you can just type 1984 and it'll select it for you.
EDIT: It does not change the fact that mobile dropdown implementations are horrendous.