you are more than right, it is actually objectively worse.

because $300K will demand much much more than 30k job.

300k job leads to stress, anxiety, performance calibrations, mental breakdowns, overwork, competition, lack of job security etc.

30k job could be very relaxed, could be part-time gig where you work few hours in a week.

so work-life balance is really tilted worse for higher paying jobs

I mean, not necessarily. A 300k job at a tech company may be less stressful than e.g. a 150k job at a non tech company with a toxic culture.

To be clear, it can be true, there are lots of stressful high paying jobs, my point is that it's not necessarily true.

I know low paid people with stressful jobs and highly paid people with less stress.

This is incorrect. If my income and expenses both increase by 10x, my savings increase by 10x. After just a few years of saving, I have the option of moving somewhere cheaper and living like a king.

It's not like your savings and investments are adjusted for the cost of living when you move.

In the extreme case, you can earn as much as possible and accumulate enough to live on indefinitely in a cheap country. This is obviously better than just earning a low salary in the cheap country for the same amount of time.

if your income 10x and you are on the wage - then that means you are either will have to work 10x more hours - or work 10x more intensively/efficiently, which leads to its own burnout and issues.

main point being is that if your income doubles, your savings rate will double, but your work related stress will double, and arguably your health (mental and physical) will deteriorate at 2x faster rate

That’s not how any of this works.