> We need to move away from the term "monopoly" (which may not literally be a mono) and towards anti-competitive.

Anti-trust rules cover both, with a (difficult to apply, but relatively well-developed) concept of “monopoly” which ultimately boils down to whether or not substitution happens in practice rather than whether there is exactly one firm ina descriptive market. There's no need to “move away” from one to the other.

https://www.ftc.gov/advice-guidance/competition-guidance/gui...