The rest is less than 15$ but you do have to order it off AliExpress. It’s more time as well so if you take it into account, I guess it comes out similar.
I would add that anybody with the know-how to build this probably already has an esp32 on hand so really only the cost of the other components should be calculated. But that cuts both ways since your example is a lot more beginner friendly and comes in a neat package with more features.