How will apps like Whatsapp work then?
I find it very weird to find, for example, my boss, or certain specific coworkers, on any social app. I don't want them to be able to find me either. This design decision of giving apps your entire contacts book by default has to die, and individual users need more choice instead.
If they are interested, then they'll find a way.
An app (such as whatsapp) getting access to all contacts is a valid use case, even though it doesn't apply to you.
I don't use Facebook nor Instagram, and I only use WhatsApp for 3 Android users, the rest of the people I talk to I use iMessage.
That appears to be impossible for WhatsApp on Android. Someone wanted me to install it a bit ago, I refused to give it access to my contacts and it refused to do anything else until I did.
So I deleted it and we used Signal instead.
Meanwhile the option remains available to use a different app that doesn't behave that way.
Your local Apple device has a messaging app (iMessage) that can see all the contacts on it.
iCloud puts contacts on Apple servers.