It just isn't an attractive place for developers. Companies (especially large ones that dominate the top50 charts) see their mobile apps as costs so they don't really care about making money there.
"Utility apps" (messengers, banking apps, etc.) do OK if the user must use them. All other types of apps are competing against the few big social apps and games that are more than adequate for most users.
The average mobile app gets opened 1 time. People have enough apps on there phone, they don't go browsing in the app store for the new new thing anymore.
It doesn't mean that people won't use apps, but the selling feature of your product being an app has no meaning any longer.
For almost all companies, it's table stakes, if you expect people to use your app on the go.
When Uber came out, being able to leverage the tech in a mobile app is what made the app possible. So that was a huge selling point of the company.
There is almost no new capabilities in phones today that allow new experiences.
So, yes, people will still develop apps. Apps themselves are not dead. The web is not dead. Web3 will be a thing, and will change some of how these things operate, but for it to truly work, I think the average person won't understand the difference between their web3 apps and their mobile/web apps.
To some the lack of "forever going to be going to the moon" may seem like dead, to others it may seem very much alive and healthy without that.
I think it goes about in waves where people make mobile sites and think that's enough, then realize that the direct hardware and lifecycle access is actually pretty important after spending a few months wrestling with certain edge cases. And then go overboard with it.
The cycles might happen in different periods of time in different ecosystems, but they also seem to be anchored around technology.
I haven't used a "new" mobile app in quite a long time must be something to that as well