Cold messages to people in my field, do they work? - any advice?

I want to talk to people in a new field but I hate cold messages. Any experience at all would help. I worry about bothering people.

I wrote three short lines: who I am, why them and a small ask for fifteen minutes. About one in four said yes.

Follow up with a thank-you and a short update. One of my chats led to a referral a month later.