I think the only choice is Signal for practical purposes. There is no creating accounts, no scanning ID's, no invite link to chat. If they already know your number, there's nothing they need for you to contct you on Signal.
For people who I have their number, I will never ever acknowledge any other option than Signal because confused people don't end up making any choice. Only if they talk about servers and networks, then I will teach them network security.
I say SimpleX F-Droid is king of them all, but for random people, I only mention Signal/Molly.
For the record, I will say that I am more willing to currently use Whatsapp than ever use Telegram. I can't speak to the cool features with Telegram because I hate it too much to register my number with them.