IMO, Side projects are about personal choice and about having fun while learning something.
The technology keeps changing; there's a need for us to keep adjusting and learning new things. But that shouldn't come at the cost of balance; all we do is 8+ hours of work and put 'x' more hours into programming/learning something that will again make sure we keep our jobs in the future.
We can pursue our passion(non-programming related), and I'm sure the community will vouch for it with their examples.
I do work on side projects but not like in a way that I would feel bad if I didn't work for some time.
I love the idea of setting 'x' amount of hours aside for learning and development. You're absolutely right, the balance should be in passions having fun, whilst also (hopefully) gaining something from it. :)
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