As someone who's been combining calisthenics + weights consistently for the last 13 years, I can, without a shadow of a doubt say, the most over-promoted and unnecessary supplement in the fitness industry, is Whey protein.
It's something you just don't need in your diet. Consuming liquid protein immediately after the workout is also so overhyped and not important for a regular person. This is coming from someone who used this stuff on the regular in the past.
I've seen how whey price sky-rocketed in the past few years thus tanking price-to-benefit ratio even more
Just eat clean and move 🏃♂️