Sort of. All that experience adds up.
In all that time I've only ever worked with proprietary tools and have never had trouble getting high paying contract work.
I would say I've done very well betting on something proprietary.
I think one of the key things is to have a passion for learning. I've always been bored doing the same thing over and over. Learning new technologies, design patterns, architectures, skills, etc is what interest me. That also, coincidentally, is what keeps me up to date and productive.