Is the advice something along the lines of once you have a couple years of relevant experience start looking for a new job that needs that experience?

Because that's how you get good increases in income at least in your early career.

Later on you'll hit a plateau of sorts where changing employers to get a raise is trickier because they're concerned about paying too much for you to come on board, so your job search will take a bit longer. But someone will probably hire you eventually for a good sized increase.