Sorry, I don't think I can edit my previous reply. Here's the edit of it.
de0u
Cellular carriers are required to track devices -- in part because of legal mandates related to emergency calls. Thus cellular networks are designed to track devices.
100% agreed. However a cell carrier tracking a phone bought anonymously and a sim card bought anonymously doesn't necessarily go back to the person despite it doing its job in tracking the device.
Consider the hypothetical situation I see (which may be straight up wrong but I'm trying to understand how this process works)
Phone purchased in cash
Phone requires network connection to unlock for graphene installation, this is performed on home network
Install graphene
SIM purchased in cash
Use sim away from home
If on step 2, that initialization process with stock android tells the ISP the phone's unique identifiers then when using the anonymous sim in step 5, the cell provider could potentially be aware that the hardware being used was associated with the household in step 2. Then it would be pretty easy to infer which member of the household based on usage patterns or device associations or whatever else could be used to track a device / person.
Maybe the network connections are never revealed by the ISP and this ends up being a non-issue but I'm not an expert in this field and again, I'm just trying to understand how it works so that I can make better decisions for myself and help inform others down the line.