30% would be around 120K per year, which is not a simple feat.
Meaning that the envy stems from the difficulty, not the amount? I guess, but then it doesn’t present as a cohesive thought. He may as well have said “my parents envy that I can run a full marathon – and, also, I struggle to afford to have a place to live”. But the implication in the article is that they are supposed to be related.
An income that does not accommodate the 30% rule, even for a meagre home, is not a decent income. It is a low income. Plain and simple. A low income that may be hard to attain, sure, but low all the same. Perhaps you could make it a decent income if you transplanted it into a low cost of living area, but that is not what is taking place here.