Second of all, there are many ways to "skill up" and that doesn't always mean creating open source side projects or experimenting with the newest fad.
After becoming a father I found I certainly had a lot less time but it forced me to cut out everything that didn't matter. That included watching tech talks, working on a bunch of small projects, getting my "commit a day" on GitHub, reading a large number of books, and so on.
Instead, I decided what I needed and wanted was financial freedom and I wanted to achieve that by building my own software business(es).
I stopped measuring myself by silly graphs or what others in the industry may or may not think of me. I stopped second guessing myself and I stopped worrying about my "marketability" or "maintaining skills" for hireability's sake.
Why worry about skills, marketable or keeping up with the fads if I work for myself? As long as I'm true to myself and I can build kickass products, I don't care about anything else.
Since then, I've built my own successful business and I am currently working on the second (second baby and second business!).