Snowflake is described as SaaS because they enforce it through communications. Given the Snowflake capabilities it falls perfectly into the PaaS layer, even by their definition: "services that provide a foundation for developers to build custom business apps" like, for example, a database with analytical and ML capabilities would. It is not an ERP, it is not a CRM, it is not a Marketing Automation tool, it's a thin layer integrated with other PaaS offerings, but anyone with an unbiased opinion would tell you just that - PaaS, mainly used for Data Engineering tasks in conjuncture with other layers of the service offering (i.e. to be used for the Software layer).