The complement play for Mistral was that they'd be the low-cost SaaS serving their own models or any better ones that the FLOSS releases created and the upsell: you prototype and develop on Mistral models like Mixtral and then when you become a big boy, you outsource hosting or customization to them (with their razor-thin margins enforced by competition). The model releases generate demand for their low-cost hosting and consulting. (Think Red Hat, not OpenAI.)

As opposed to an all-inclusive API where the pricing can be as high as the consumer-surplus with very fat margins, because it's all-or-nothing.