To not be annoying the tools don't have to just exist somewhere, they need to be ubiquitous. For example, If I'm looking to upload an image as an avatar on a website, will webp be supported? It's unlikely, even if the site itself might ultimately serve up a webp file. So then I'd have to use a tool to convert it to a more ubiquitous format before uploading it, likely doing a bunch of lossy conversion along the way. That's annoying.