If you earn 100,000 net per year, you most likely do not need such an insurance, unless you want to insure something else like a yacht or similar gimmicks.
What does all this have to do with earnings? If you have a loan of an amount X and let it run for Y years, you would need insurance for this period. If dead, then usually no income and the other party is left in a difficult position.
Anyone who earns €100,000 net per year does not need to insure a €300,000 financing. Or do you also insure every nonsense with the small car financing?! That someone with a €100,000 net annual income doesn't set up a €300,000 shed is another matter.
The numbers are far-fetched. Otherwise, such a protection has nothing to do with the income. Of course, you can consider differentiating if one party earns less and the financing can also be borne alone. That’s why we only have one risk life insurance for my wife.
I see it the same way, that has nothing to do with the income. Who can and wants to afford something (house, insurance, ...) is different for everyone ... Those who earn a lot may have to and even want to secure a lot ...