Valve Says It Will Now Allow Everything on Steam Unless It's Illegal or "Straight-up Trolling"

[Chazore]

Hiku said:

On their platform?
You can't go into a physical store and expect to buy any product you want. You can only buy products that the store endorses/carries. While that's not always a case of quality over quantity, if they don't want to sell a product because they think it will cause customer dissatisfaction, whether it's due to poor quality leading to complaints or something else, it's perfectly normal if they refrain from doing so.

Steam is a private company and has the philosophy that they do not want to tell you what you can/cannot buy. 

What is quality to someone, will be garbage to another. it is a subjective issue, not an objective one.