It’s unclear how ISPs will be affected. From the article:
The ban is just on consumer routers, right? What about the routers and cable modems my ISP rents me, my pocket hotspot, my network switch, my Wi-Fi extender?
It could affect all of those or none of those.
The FCC is banning “consumer-grade routers” as defined in NIST Internal Report 8425A. These are routers “intended for residential use and can be installed by the customer.” But it also defines routers loosely as devices that “forward data packets, most commonly Internet Protocol (IP) packets, between networked systems.” That could cover every piece of gear you use to connect to the internet or even your home network.
Companies get to self-certify whether they’re adhering to the rules, can claim whatever they want, and then it’s up to the US government to inspect at customs or not.