My experience was L5 always seemed like the happiest engineers. It has often the most interesting technical work, still great pay, and low stress (compared to higher levels at least). It seemed like when people got promoted to L6 their overall quality of life would go down. I knew a lot of people sticking at L5 on purpose (I once even talked to a CTO at a small company who said they had wished they never were promoted above technical lead).
L5 is a great terminal level (and the equivalent at other companies). you are trusted to walk and chew gum at the same time, can cause meaningful damage (good and bad), and largely “too lowly” to be in the perpetual pissing matches of mid/upper mgmt. sure you won’t control your own destiny in broader projects but it’s a good life you often don’t miss till you’re past it.
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.
It's great that it is terminal, but both comp and the respect you get in the company is strongly affected by level, so it's hard to just sit at L5 while you watch your peers rise the ranks
