But what we know for certain is that Lightning Network is not widely used where it is expected to be used
It isn't widely used
yet. That doesn't mean it is somehow
broken or dysfunctional. Lightning is pretty much still brand new in the grand scheme of things, and adoption takes time
Well, this is not what I meant
The problem is not with Lightning itself but rather with "the grand scheme of things" as you put it. In other words, even if it is brutally efficient on its own (fees and all), it can't further something when there is nothing to further. You see, there are only 21M bitcoins and given that, why would folks want to spend their precious coins? No way if you ask me
In this manner, OP is technically right, though not for the reasons stated. Bitcoin is inherently deflationary (despite its total supply still increasing), and no Lightning Network is going to change that. Long story short, people don't spend gold, digital or otherwise. That's why it can't serve the world as it is more like the world is to serve Bitcoin