My friend. You have chosen an answer. IDK if it was the correct answer or not bc both answers lead you here regardless.
EEC.
Short for Educational Email Course.
"That sounds lame or boring" you might say.
To which I would reply "you are lame and boring and you must not like money."
EEC's solve your problem of low opt-in rates.
For example - Which looks better below?
One is generic. One is specific.
One is vague. One is solving a problem.
One offers no value. One offers a ton of value.
An EEC lives on your webpage.
It gives the potential client another option to click besides "book a call" AND solves a problem for them.
Once someone enters their email, they are then emailed something extremely valuable several days in a row, and each day builds off of the previous day.
This creates trust between you and the potential client.
This teaches the potential client to open your emails.
This allows you to now have that client on your email list for future email campaigns (hopefully newsletter at the minimum).