I see the theoretical need for such fingerprint displays, but I can't imagine noticing that the display for one of the computers I work with has changed. Maybe if I printed them all out and posted them around my monitor...
I've found setting an alias like `alias ssh='ssh -o VisualHostKey=yes'` makes these fingerprints appear on every connection, creating muscle memory for how they should look. When something changes, it immediately feels "off" without needing to remember specific patterns.
Why not use ssh's config rather than an alias?
I wonder if this would work better if it played a little jingle on every connection, rather than showed a picture.