Does Hyvä Commerce Media Optimisation replace Cloudinary?

For most SMB and mid-market stores, yes. Media Optimisation runs on your own server: it converts uploaded images to WebP and AVIF, resizes to admin-configurable max dimensions, and serves the right format per browser, no external service, no per-image cost, no bandwidth fees. The trade-offs vs Cloudinary are: (a) you handle the compute, (b) no on-the-fly URL transforms, (c) no DAM features. For a typical product-catalogue use case, those don’t matter.