[gear54rus]

Perhaps you'd be interested in learning that you can initiate chats to phone numbers (regardless of contact status) by going to wa.me/<phone-number>

I've never tested it without contacts permissions though.

[throw-the-towel]

They broke that just several weeks ago, at least for me.

[dvdgsng]

Same for me, has been broken for about 4 weeks.

[wodenokoto]

You can send the phone number to yourself in chat and then click it to open it for chat.