Yeah, that part about skill improving really hits home. I read an interview with an astro photographer who said the biggest jump came from learning to stack dozens of images in software, not from a new lens. They stressed that all the fancy gear is wasted if you don't know how to pull the data out of it.
My first real camera was a used Nikon D90 with a kit lens. I spent two years learning light and composition before upgrading anything. The jump in my photos from that old gear to my newer setup was huge, but only because I knew what to do with it. Better gear just lets you do more of what you already know. A fancy camera in auto mode still takes boring pictures.