Thanks for sharing this! I saw it when I was a corporate leader, too. New hires often came in at a higher base salary than tenured employees.
I'm a career coach now and I always tell my clients that it never hurts to respectfully negotiate hard. Your compensation bumps are always the biggest when you start a new job.
Also, staying in a company for too long almost always means you're making way less money than you should be. Internal raises are limited and throttled (e.g., size of raises, number of promotions).
If you're not moving up consistently and compensated well, you have to move on.