I found the most easy way to motivate people to switch, is to just remove your WhatsApp profile-picture and set your status to something like "Find me on Signal".
The amount of people reaching out via WhatsApp lowered drastically, all (but one) of my main contacts are now also on Signal.
The amount of people reaching out via WhatsApp lowered drastically, all (but one) of my main contacts are now also on Signal.