The parent's point, I think, is that teachers and firefighters (in this country) are rarely (effectively never) compensated according to the value they provide. I happen to agree with that point.
Yeah, compensation matches the number of people you reach in the moment, rather than the impact of that reach. Those who reach millions of people (rockstars, football players, the person who designed the curve on a button at a hot tech company, vacuous reality TV stars etc...) will earn relative to the audience size at the moment of earning rather than the value-add-per-person.
Teachers and firefighters have immense value on a very small number of (often unappreciative) people directly. The outcomes from that value might be immeasurable, but at the point of delivery, society doesn't value it highly enough for heft compensation at present.
