Most exhaustion at work is not from the work. It is from the accounting. Who noticed, who did not, who took the credit, what it means for next year. The task itself is rarely heavy. The ledger is.
Karma yoga proposes something unreasonable: do the work well and let go of the receipt. Not indifference to quality — the opposite. When the outcome is not carrying your identity, the quality usually goes up, because you are finally looking at the work instead of at yourself doing it.
On karma yoga, credit, and why the best work in the world is usually unsigned.
This is not an argument against ambition or against being paid properly. It is an argument against doing every task twice, once with the hands and once again in your head at two in the morning.
Test it for one week on one small task. Do it well. Tell nobody. Notice what is lighter.