Somewhat new to navigation and I'm curious of the purpose / point of "waypoints" like these shown here that have no radio to tune into. How are they generally used and what are they for? Seems like there's sure a lot of them in one general place...?

Those are waypoints (RNAV), points defined by coordinates that are used for navigation.

There's an interesting article of a pilot explaining what waypoints are - CN Traveler - A pilot explains waypoints and a brief definition on SKYbrary

Hope that shines some light on that question for you.