A targetted SMS interception attack looks like something something SS7 or SIM swap/social engineering, but a wide net attack looks like pwn the telco and get ssh access to an SMS gateway (or logs, or a database with content), or an aggregator, or a middleman SMS provider between aggregator(s) and carriers, or posing as a legit (or grey route) middleman and getting in routing and then snooping on stuff. Or just a highly priviledge position at a carrier or sms aggregator.

If your wide net lets you see 2FA codes, sometimes you can do stuff.