Economies of scale of production of telecom equipment are considerable. There are only a few manufacturers and most countries rely on foreign suppliers. But there are concerns about surveillance being built into the equipment itself, enabling the governments of the countries where the manufacturers are located to spy on others. This issue has come to the fore now as Chinese suppliers are increasingly displacing Western companies. PCMag, a US publication, provides a useful analysis:
Network equipment is, in general, where spying happens. You can dragnet a lot of communications at once, it’s jealously guarded by wireless carriers, and independent researchers often don’t have access to it. You don’t even have to have special backdoors in the network equipment to spy. The well-known SS7 network flaw is widely thought to be used by intelligence agencies around the world to spy on cellular traffic.
When the UK and Australia have criticized and blocked Huawei in the past, it’s always been about network equipment. Australia banned Huawei network equipment from its national broadband network and then issued both Huawei and ZTE phones to government staff members, demonstrating the huge difference between how network equipment and phones are seen.