1) bare metal is dramatically faster than most cloud instances. Many of us might have collection of old hardware that, by performance, would be equivalent to >$1,000 in monthly cloud fees.
2) If from the start of your career you have only dealt with modern cloud/Azure/AWS, there is a whole body of knowledge you are missing. Acquiring it from scratch is time consuming, and you are never quite sure you are doing the right thing. As a developer, I don't pay the AWS bill, so it would be more rational to spend my time on learning ML or something else that will be reflected in my paycheck.