Credit card income requirements - do banks strictly follow?

No. Although no one will admit this.

Credit card salesmen/women are very incentivized to make sure you get your card application approved.

Banks business relies on people incurring credit card debt, whose interest rates are more than 20% annually.

No need to blame the system for being easy. Unsecured debts like credit card debts are a “takes two to clap” situation, people rather take on debt so that they can #hypebeast or carry the latest phone or be seen wearing AirPods.

This situation very prominent in China and South Korea now. Anyone there on holiday will notice that they wear a lot of branded goods. And somehow they are now quite against counterfeits.

Not necessary, I know a friend who was self-employed (usually hard to get cc) yet OCBC CSO calls him and offer him 2 CC. It really depends.