I've found the opposite of this sentiment to be true, at least in my case as youtube engineer / maker. If you can find a way to monetize your hobby it is:
1. A great motivator to actually finish projects
2. A good way to justify / fund more costly projects
3. A great source of joy if people enjoy what you make
I've been careful to not undermine my key sources of joy in making things (learning, doing hard things, making quality things) by keeping monetization at a lower priority to those things. In my opinion if you can find a way to monetize without undermining what you truly enjoy, you can thread the needle between job / hobby and I'd highly recommend it!
1. A great motivator to actually finish projects
2. A good way to justify / fund more costly projects
3. A great source of joy if people enjoy what you make
I've been careful to not undermine my key sources of joy in making things (learning, doing hard things, making quality things) by keeping monetization at a lower priority to those things. In my opinion if you can find a way to monetize without undermining what you truly enjoy, you can thread the needle between job / hobby and I'd highly recommend it!