Kinda apropos, I’ve used international data roaming in mainland China and was (initially) astonished to find it totally bypassed the GFW and I could run IPsec and SSH unencumbered, none of the unabashed MITM fuckery I saw from using strong crypto over Chinese hotel wifi for more than a couple of seconds. That was a few years ago, I don’t know where their interception regime is at today, but it was a reminder that propaganda begins at home.
LTE and 5G standards allow end-to-end encryption of the roaming traffic. So, it's by design. If your operator chooses to enable e2e (and usually they do), there would be just two options: block your traffic entirely or let it pass as it is.
