I don't have a phone number. My SIM card has only a data package.
In the context of privacy it mostly means you can't easily link my accounts trough my phone number.
As of why is a long story that mostly resolves around how bad and annoying a phone number as security measure is and how you have no way of actual owning your own number.
- only using my own cloud (NAS, Home Automation)
- heavily filtering internet (Pi-Hole or AdGuard + ublock when possible)
- no public social media (FB, Twitter, discord, whatever)
- Only throwaway accounts on some social media
- Not having a real phone number
- Using rented throwaway phone numbers when necessary
- Only use credit card for a few trusted services.
- Avoid services with questionable business practice (Forced 2fa over SMS being one common reason) but also things like Amazon, Microsoft, ..