For sure this. I had a really strong team of engineers, maybe the best in the state where I live, and through their tough code reviews and just picking up things through our discussions, I've improved drastically within a years time.

At a prior job, I was benched some of the time, then put onto a project with a "wild west" coder as my senior, then left by myself to handle the entire project. Lots of lessons learned there too, but having a supporting team to guide and work with made me grow 10x faster than just having to "figure it out".