Fitment is an asset, and assets should be yours
Product data you can re-export from Shopify any day of the week. Fitment relationships are different: they take months to assemble, they encode knowledge your staff has and your competitors do not, and in a vendor-database app they live somewhere you cannot query. ViewForge writes them as Shopify metaobjects — native records, readable from the Storefront API, exportable through Admin GraphQL, still there after you uninstall.