Our view
One data model instead of a sync
The argument for Commerce Cloud is rarely the storefront in isolation. It is the removal of an integration layer: customer, order and service data sit in the same platform as your support and marketing operations, so a service agent sees order history without a middleware sync, and segmentation reaches commerce data directly.
If your business does not already run on Salesforce, that advantage largely disappears and the comparison becomes much closer.
How we scope it
Commerce Cloud licensing is usually tied to gross merchandise value, so the business case is sensitive to revenue projections in a way flat-fee platforms are not. We model that against Shopify Plus and Adobe Commerce during discovery rather than after.
See platform migration for how a move is structured, and unified commerce for the store and marketplace side.