Help me double-check my replacement equipment.

Is the whole concept of an anode just snake oil or is there a better way to handle corrosion?

Corrosion of what?

Anodes have a place on boats where you have galvanic corrosion. A properly designed pool does not have dissimilar metals.
Just balance your chemicals?
That is a good start.
 
14. Manual union ball valve
Get rid of any union ball valves, Install diverters.
Is the whole concept of an anode just snake oil or is there a better way to handle corrosion? Just balance your chemicals?
Vintage Salesman GIF by Challenger