Curiosity arises from lack of feed
Here's a hypothesis: I think I'll always find something I am curious about. I am a naturally curious person, and I would actually guess that everyone is? It seems impossible that there would ever be a moment where nothing could interest me.
But I think curiosity arises from lack of Dopamine. Basically, boredom. If you never allow yourself to be bored, or even close to that state, you won't be curious either. It's so easy to cover up curiosity, to suffer it. For example, by scrolling Twitter / Facebook / Youtube / your-favorite-feed. If you do that, you give up self-direction. Instead of looking around the world and going in a direction you find intriguing, you simply receive what others think should be on your agenda. In the worst, and probably most common case, you simply follow whatever is put in front of you by an attention-maximizing revenue machine, and that will define the lens you will see the world through.
That seems actually pretty grim, but I think it is common. There have been many, many periods in my life where I've lived exactly this life, simply consuming algorithmically curated feeds (or, only slightly less nefariously, editor-curated feeds in newspapers). And I see this in people around me, too. Whenever a free moment arises, a feed opens up.
The word we use, feed, is actually grotesque if you think about it! It's as if you're a chicken in a cage, and your body lives off of whatever the conveyor brings to you. It is, of course, and extreme description. But perhaps thinking of that extreme gives strength to exit the conveyor occasionally, notice that the cage door is open, and wander outside for a moment. You might discover that the cage, in fact, is only in your own mind.
I suspect we're most susceptible to the feed when we're in periods of high stress. Sleepless, working a lot, or otherwise under lots of stress. It's often hard to break out of these situations for objective reasons. The feed is always the easier choice. Weirdly enough, it's even easier to open the feed when tired, instead of going to sleep. I wouldn't expect that! The feeding part of my brain has such superpowers that it can override fatigue, when the math-learning part of my brain completely fails at that.
Contrary to what it might seem based on my bleak descriptions above, I don't judge you if you're feeding that way. I often am too. My gentle suggestion would be to simply notice, without judgement, when that happens. Non-judgemental awareness is curative.