Android: What are the disadvantages of using a lower minimum API level?

So i’m approaching the release of an game for Android and wondering what minimim API level i should select. Right now Unity defaults to 19 (Android 4.4), but i’m considering to use 16 (4.1) which is still installed on ~15% of Android devices.

Of course i want to reach as many as possible potential users, but what are the downsides of choosing a lower minimum API level?

It is Graphics APIs, runtime upgrades (remember when KK made dalvik not the default runtime), permissions and (not sure, just a speculation) possible promotion willingness on Google play store.

Android 4.1 version users probably run slow phones with very poor performance.