You’re wrong here it’s the most vital and not minor part actually, because it collects the most important thing - your actual identification:
-
Once you insert SIM card - you’re forever linked your device IMEI / IMSI unique numbers to your actual government ID.
-
Government already knows your ID and exactly who you are and likely everything about your personal life (because all the usual privacy violators share all the data with 3rd parties for cash), so by combining it with geolocation they’ll know exactly who and where you are.
-
Combined with all the other spyware, GSM and Wi-Fi triangulation, Bluetooth-LE on most phones, except GrapheneOS where you can actually kill it - they’ll know your exact position to an inch.
-
Now imagine if you’re also an absolute normie who uses social networks and proprietary software at the same time with everything i’ve mentioned above…basically it’s glowing agent inside your pocket 24/7.
My point is - all that data without SIM card / IMEI /IMSI leaks - is not really much to anyone.
So yeah, even if let’s say you use “old looking” burner phones without being smart about it - you will get immediately burned by just inserting SIM inside it, besides new “old looking” phones have even more spyware baked in them, than Android / iPhone (which i find surprising, but not really 
)
Well you actually don’t have to live a life of paranoia with GrapheneOS, it’s very easy to use.
And yeah, privacy really worth it…all that convenience vs privacy is a propaganda false dichotomy.
If you know the implications of loosing privacy - it’s like being constantly raped…is it really as convenient therefore?
Maybe for some people it is, i don’t know.