> If you are sending cold emails to people you know will be interested, that’s fine.

This is my rule. If I gave you my info at some time, and you have a new product you think could be relevant for me, fine. If you got a contact list from some convention, and are shotgunning it with "We sell X. If you're not in charge of Y, please direct me to the appropriate person", I'll report it as spam faster than The Flash.