A $300 lens is objectively better than a $5 smartphone lens.
A $2000 lens may be objectively better than a $300 but it depends what you're standing in front of and you.
The Nikkor Z 28mm f/2.8 is my favourite so far and it wasn't exactly expensive.
The priority order for things is of course:
1. What the photographer is standing in front of
2. The photographer
3. The lens
4. The camera
But, at least today, you still get enhanced features on the more expensive zoom lens, such as wider aperture, and a constant maximum aperture across the entire zoom range. Neither of those things necessarily yields a superior photograph -- you don't need f2.8 across the whole zoom range if you're taking pictures at f6 -- but they can be very helpful. If they're worth paying for depends on one's personal needs, desires, and budget.
Not sure where you are getting the $5 figure from. In any case, smartphone lenses are manufactured in vastly higher quantities than lenses for interchangeable lens cameras, so it doesn't make sense to compare the per unit cost. Modern smartphone lenses are miracles of optical engineering. See e.g. https://news.ycombinator.com/item?id=30557578 The cost of the R&D that's gone into enabling their design and manufacture probably couldn't have been recuperated if they were being used only in cameras.
On the flip side, my favorite macro was a Sigma 105mm prime. Tack-sharp, and cost well under $1000. Of course, I’ve never shot with the equivalent Canon L (which isn’t quite the same at 100mm, but close).