I'm not going to refute the rest of your comment, as it's a valid opinion and I'd just be repeating myself, but in regards to this:
>Once you get settled into a career it can be really hard to step back out into solo dev.
I don't think that's true in and of itself. A lot of people struggle to adapt to the financial uncertainty of flying solo later in life, but that's only because they have a high-cost lifestyle and minimal savings.
I quit my day job last year, a few months before my first daughter was born, to run my online businesses full-time. The fact that my wife and I had saved huge chunks of our pay (100k+ in the bank), in addition to the fact that the businesses were already running at half-steam meant that the transition was stress-free and seamless.