I don't think anything has hurt me as much emotionally in my career as working at a really great place as my first job, setting my expectations for the next ten years of my career to be anything like that, and then get curb stomped over and over again by mediocrity that thought it was objectivity or responsibility.
Trying to mold people who did not want to be molded resulted in a lot of Pyrrhic victories.
If I hadn't moved to a new town, and if they hadn't also, I would have tracked down some of my old coworkers and asked them very nicely for a job. But we all 'graduated' and flew away.
I just worry that if I stay for years, and then for some reason do have to leave, it'll be harder to find a new job with my first as a dev having been at the same company for many years.
Generally I think long tenure is a positive signal, but you have to be growing. If you are growing and learning, and enjoying it, I recommend you continue to do so. Stop and smell the roses while you're at it.
In theory, skills are what matter, but I don't find that true in practice. Appearance matters more. A long tenure is a good look to most.
Trying to mold people who did not want to be molded resulted in a lot of Pyrrhic victories.