That is not correct. The return policy is effectively part of the sales agreement and can not be modified after Purism has been paid. It’s a contract and corporate status has nothing to do with this. Also, the FTC Mail Order Rule applies uniformly to every US corporation. Please don’t spread misinformation.
The only “rule change” for an SPC is in regard to shareholder expectations. In the US, companies can be sued if they act in a way that is contrary to shareholder profits. If you are an SPC, the corporation can sacrifice shareholder profits if they are doing so in order to follow the social purpose stated in their articles of incorporation ( https://puri.sm/about/social-purpose/ ). Of course it also requires Purism to file a Social Purpose Report annually which documents the choices they made in following their social purpose —> and Purism hasn’t ever filed one, so they are not really protected by their SPC status at this point.