There's plenty of things you can be simultaneously worried and optimistic about, and I find this is constantly true of parenting.

I will encourage my kid to gain independence, but of course I'm worried about it! The fact that there is uncertainty in her independence and that I can imagine bad outcomes does not mean I'm working against her interest by encouraging it.

"I don't know what jobs there will be to do" is a statement of uncertainty, and, given how you are relaying it, there must have been fear there as well. But it doesn't seem like it's a statement that the world will be worse. You can be fearful and hopeful at the same time, and fear tends to be the stronger of the two, and come out more strongly, again especially in parenting I find, even if you find the hopeful outcomes more likely.

I’m with you. Your example is little squishier to me but I am a parent so I understand your point.