[lucideer]

On the contrary, this seems like too kind a stance for npm to take. The approach Microsoft took here seems enormously and unnecessarily inefficient.

Microsoft maintain the @types scope. Instead of providing their own metadata endpoint listing available typings to filter requests on, they lazily opted to just mass bombard a repository they maintain, hosted on a free service they don't fund, for any and all possible package names, even though they themselves maintain the list of packages and should know in advance which don't exist.