Portable LTE Router instead of using your SIM card in your phone?

Is there any benefit to using a portable LTE router, connected to your phone via ethernet? As opposed to connecting to the cell network using your phone directly? This assumes you're away from home, and you don't have access to public wifi.

Among the benefits that I can think of, is you would be masking your phone's IMEI with that of your router. If the router is cheap enough, you could buy many of these.

I'm using GrapheneOS. It seems …

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