I question the validity of that chart. RM37k per month for T1 is quite low. There are many people I personally know that earns much more than that.

business owner earn a lot meh?

private doctors earn minimum 50k a month, one of my family friend 150k a month as urologist

Yes I am referring only to salary workers.
I can attest to that. Surgeons at a private hosp can do RM200k a month.

Not sure I understand your question.

It's not limited to surgeons. I only know a few doctors and was responding to another comment on surgeons.
Many business owners also fail. In fact, majority of those who started business has likely failed. A few of my friends who ventured into business has failed (corporate gift service, team building/event company, etc) We only hear the success feel good stories online.

That guy I referred to earning RM200k monthly.. He has worked as a doctor for >20 years before getting sub-specialized. Now reaping the rewards at late 40s but still working non-stop. No time to spend with fam and kids.