Starting in Firefox version 142, Mozilla released a “Link Previews” feature.
While the feature is problematic, commenters pointed out that some previews are helpful – e.g. on Wikipedia, where a preview will appear when people hover over a wiki-linked page.
Other commenters pondered about some minimal way to replicate this elsewhere, and it seemed to be worth investigation. Read on as I propose an enhancement to the Fediverse (and maybe even web standards) to make Link Previews great: the Link Preview Manifest.
I think the previews should be federated along with the activity. The main issue described by itsfoss and the mastodon bug is not about previews themselves generating a lot of traffic but federated nature of fediverse multiplying the number of requests. If along with the post/toot/w-v the preview got sent out too, that might ease the load on the publishing host
One thing that I neglected to mention is that since the SRI hashes are calculated, previews can be cached by peers other than the originating host - since they are verifiable, anyone can pass them along and the client can verify the payload.
Not something I really fleshed out in discovery, but if there is interest, that might make it more production ready.