The problem with cold calls is that you expect random people to stop what they are doing and listen to an advertisement; often for something they don't want or need.

Whatever you interrupted is far more important to them than whatever you're selling; especially if you haven't introduced enough filters in your process to ensure you're calling the right people.

We should either ban cold calling completely or introduce enough friction to the process that cold callers are incentivized to more closely filter who they call. (IE, I get cold calls trying to sell solar panels. The caller knows my address, and can see the solar panels on my roof on satellite photos. They just shouldn't bother calling me.)

It's because there's an imbalance of cost: It's cheaper to just nag me than to actually research if I've already bought the product or are interested in the product.