It is important to understand that those salaries aren't normal.
300k for a new grad is not something I've heard of, that's a tad high even for phds. For an undergrad, that would be something approaching an acquihire. That person is being hired for a specific and rare skill, not as a back bencher. A lot to live up to.
Even 200k is very high for new grads. Think "strong student at MIT/Stanford/CMU with proven track record of performing very well during internships, maybe some research publications, and multiple internal stakeholders vouching for them". In other words, perceived as "potential deadly weapon to a competitor and/or a possible founder", not "model employee". That is why they're being paid well.
Below 200, keep in mind that 150% of 80 is 120. SF sucks. NYC isn't much better.
Teachers are underpaid. Not sure how that's relevant to whether some other group of people is overpaid. It's not zero sum.
As for researchers, in CS they do well for themselves. Don't worry.
I think you are conflating what is possible with what is normal, and in the process under-estimate the amount of time and effort some people choose to invest into themselves during their 4 years of access to the best and brightest minds in their field. Speaking of, MIT gets disturbingly close to 6 figures all in these days...