Why wouldn't you? It's a number. It's also sorted (up to about one second of inconsistency between Twitter worker processes on different machines), and you want to sort them by numeric sort, not by lexicographic sort as you would with strings.
I mean, there's a pretty clear argument here: Twitter themselves used to return these numbers as numbers in the API until they realized they were about to hit this problem. https://developer.twitter.com/en/docs/twitter-ids
Using numeric types as ids probably leaks into other areas, where being numeric is then assumed. When you want to change it at some point, you got to be very careful suddenly. A string could simply contain a new kind of id. Seems less refactoring effort would be required. On the other hand, switching from numeric to strings might give you compiler errors when types do not match, so perhaps it might even make refactoring simpler.
You can always add a second or third key. Stop messing with the primary key. Many systems have a numeric primary key and then only expose a hash or UUID to the public.
