The national median software developer salary is something like $110k. The middle 50% range is like $85-150k, so if you're making above 150k TC you're already in the top 1/4 of developers, who are already very high up in general.
I say this because people on HN love to pretend that "industry-standard" means $250k+ for new grads and $400k for experienced ICs when that's just not true. FAANG-level salaries (which can absolutely be 300, 400, 500k TC) are the 1% of the 1%.
It is definitely unreasonable to compare a Mozilla engineer’s pay to an average brought down by body-shop CRUD operations. They’re really not the same industry.
Mozilla is going against FAANG products like Chrome. Compared to the competition their salaries are tiny.
FAANG & companies that pay similarly employ something like 8-10% of the engineers in the country, so this is an enormous overexaggeration. We can quibble about whether it's reasonable to represent that as "industry standard" or not, but it's not such a drastic outlier that it becomes unreasonable to use it as a point of reference when discussing things that might be reasonable to aim for (or expect, in certain contexts).
I'm not sure where you're getting that number, but it's much too low.
The figures at https://www.levels.fyi/company/Mozilla/salaries/Software-Eng... better match what I saw when I worked at Mozilla.
You can compare compensation at equivalent levels for Mozilla and peer companies at https://www.levels.fyi/?compare=Mozilla,Microsoft,Apple,Goog... . You'll see that Mozilla pays well, but significantly less than them.