It's hard to imagine another policy without making it excessively difficult for vendors to add new features. For example, a button on a laptop that changes Wifi

It's hard to imagine another policy without making it excessively difficult for vendors to add new features. For example, a button on a laptop that changes Wifi configuration might need a similar driver program. Hardware vendors are generally expected supply their own drivers for all but the most common built-in devices. This can include user-mode applications. The driver certification process has greatly improved the quality of 3rd party kernel drivers. In my experience BSODs are really rare these days. But obviously there can still be quality-of-implementation issues. This sounds like a question of "is this really a good use of RAM from the users' cost/benefit perspective?" Disclosure: I'm new at Microsoft but my role has basically nothing to do with this stuff. Just my personal opinion as a long time developer and industry-watcher.