It's easy to be underleveled at a BigCo job, and to not even realize what that means because the leveling system is obtuse from the outside. You can spend many years fighting the bureaucracy just getting your title/comp to catch up to your skills.
One nice thing about being <= L5 is that your vacations are actual vacations. I can disappear for months, totally ignore my email, and have nothing be on fire when I come back.