Maybe he thinks more than one company is sufficient then? But that’s still just a civil difference of opinion! It’s not insulting to be disagreed with I’m afraid.
Except in the context he is speaking of, extremely few Americans have more than one company supplying them with Internet access. It is definitionally a monopoly, and to say existing anti-trust legislation is sufficient is saying the monopolies as they exist now are acceptable and nothing needs to be done.
It is a dismissive comment from the senator, he should feel insulted. It is like saying "help I'm bleeding" and the guy next to you saying "its not that bad, get over yourself".
I'm not so sure monopoly captures the root of the internet access problem. Yes, in many markets there is a single provider (e.g., Comcast). There are other providers (e.g., Verizon). But neither enters the other's markets.
I'm not suggesting their is a spoken conspiracy. But when neither side benefits from direct competition, what's the word for that?