This was a fun circuit to design, and it's not entirely frivolous!

In these times of chip shortages, it can be very useful to base a design on bog standard generic parts that are produced by many manufacturers, such as the 555 and TL431 used in this design, versus doing a design requiring specific components that may only be available from a single source.

You can download the file and play with it in LTSpice, it's a fun way to learn about simulation, and it can give you a nice feel for how the circuit works.  Try to change the input voltage V1 or source resistance R5 and see how it affects operation.  Or vary the load and see what happens.  Or change R3 and see how it affects the MPP voltage.

I don't really have any plans to turn this into actual hardware, but it's tempting just to see how well it works in reality.  I guess I may do it if there's enough interest!