key=value is a convention used in so many places that have nothing to do with form encoding

Would Java developers see this and imagine you're passing values for a .properties file?

If you've never seen the tool before, you also wouldn't know how it works at all. Once you hit help for the first time (you know, to actually learn how to use it), knowing it defaults to JSON is pretty much a base truth.

It's entire value proposition seems to be stongly tied to JSON support (2nd highest feature in the pitch at the top).

This is like saying you'd forget jq takes JSON strings...

How many key/value formats commonly used for http request/response transactions use = ??

The first feature pitch is “user-friendly curl alternative with intuitive UI”.

I'll leave it at this, I'm glad they prioritized not having to escape JSON on the command line over people who have no idea about how the tool works being able to guess how to pass form inputs.

That is probably the most user friendly difference they could make for working with JSON based APIs

Right, but this is HTTP, which has used form encoding since... 1998, if RFC 2388 is to be believed.

That doesn’t sound right. I’m pretty sure it’s older than that. New RFCs tend to replace old ones and I don’t think they reliably make it painfully obvious this is what’s happening.