Psilocybin mushrooms are illegal, although recently, some municipalities have started to decriminalize them. However, Psilocybin decriminalization is not synonymous with the legality of using and commercializing these mushrooms.
Growing magic mushrooms for personal use or with the intention of selling them was considered a felony and punished according to the law (which is not permissible at all!). You risk spending years in prison and paying very high fees for dealing with such illegal substances.
However, these mushrooms can be grown for research purposes, and the commercialization of spores is legal (spores do not contain psilocybin!). But you must be careful because as soon as mycelium starts forming from the spores, the legal status changes to illegal. The best place to buy mushroom spores with unique pharmacological compounds is from a lab with stringent standards.
If you want to find the proper legislation and understand all the legal aspects related to magic mushrooms, you must find reliable sources. Not for nothing, but the problem is quite complicated. Some aspects differ from state to state. If you fail to comply, you risk serious problems with the law, like psilocybin, under the Controlled Substances Act, is a Schedule I substance.
You can read the proper legislation and accurate information on the legal status of psilocybin mushrooms on various websites.