For example, I have recently started doing a lot of cooking and bread baking, and I've watched hundreds of youtube videos about those topics (which I could argue demonstrates curiosity), but I still haven't bothered to learn React or Angular because I barely have to deal with javascript in my current job, and where I do, jQuery usually works just fine for my limited needs.
When employers say they want someone who is "curious", what they are really saying is they want someone who is willing to spend all their personal time self-educating on programming topics, effectively making themselves more valuable from an employment perspective. The employer, of course, is rarely eager to actually allocate "learning time" during normal business hours, and is rarely willing to give you a meaningful raise when you actually have self-educated on your own time.
I really wish more companies actually TRAINED their employees DURING BUSINESS HOURS instead of just trying to hire "curious" people.
I've done this for decades, and there's a degree of regret about how much time I've spent 'learning' and 'being curious'. Not a huge regret, but... it's help reduce the need to dive in to some things altogether. But.. that comes across as "not interested in learning" to some people. No... I can usually just tell after a quick skim if there's going to be business value in tech X. We don't need to spend weeks prototyping something that is obviously not a fit... unless... we're doing this for show, or politics, or something else. If that's the case, just say "we're using X" not "let's investigate X to see if it can meet our needs".
Good on you for having non-tech hobbies. I doodle on guitar, and am 'curious' about that, but it's not going to land me any tech jobs. :)
1. (Curiosity) How do you keep up to date with tech? Then explore something recent they started playing with and how they found it.
2. (Ability to learn) Ask about past failures, what they thought went wrong and what they'd do next time. If that's a bit harsh, ask what they'd change about their last major project.
3. (Ability to listen) For me this is about how they work with others, so probe for areas of friction they've had, particularly with people outside their immediate team.
You can't discount bias, but you get a baseline over a few interviews and can go from there. It's worth pointing out that all of these are soft skills, and quantifying those is always hard. Sometimes you've just got to trust your gut. It also helps if you've spent time working in a customer focused job, because you tend to be better at spotting egregious personality flaws.