That's not actually related to Magic Wormhole, it's "inspired by" it.
It's a frustrating naming decision, to be sure.
Then it's not secure.
You seem to be missing the point. If I wanted to send a funny webm in a room on Discord or IRC for example, if I didn't want to upload it directly to Discord that is, I could use this with ShareX to upload it and get a link that's easy to share. It's not supposed to be secure. It has its place alongside Magic Wormhole just fine.
If you want to send a funny webm, use whatever you'd like. The comment to which I responded to said "no, this isn't the same use case, because Magic Wormhole makes you install something". If they'd said "this isn't the same, it's supposed to be OK for this to be grievously insecure", I'd have shrugged and moved on.