I've come to appreciate the "when X is not the right choice" that some projects list. Even if it's the right choice it often provides additonal information because it deliberately takes a different perspective.
Related to "being honest" are the many bullet points some projects lists as features only to have you discover very much later that it's more like a roadmap without saying so. Just be honest when you describe your project because exaggerations will only lead to frustration among potential users.
Examples of things that might be true (I do not know how true this is! Inferring off of what is seen, and I am not judging Pony on any level)
- "prototyping UI work in Pony will not work, as there are no great known patterns for writing small UIs that play well with the consequences of our design decisions prioritizing correctness"
- "our actor based model works well for the vast majority of highly concurrent programs, but can make realtime systems hard to get right" (I have had this experience in Rust trying tokio vs just opting for manual threading)
- "restrictive syntax means that solution spaces involing DSLs will leave you wanting."
I think everything is good and great, but it's valuable to lay out the priorities and what are less of a priority. Of course tooling kinda sucks for newer languages. Of course! Tell me about things that will likely always be a bit miserable.
What they've done instead is they've explained why you might want to use pony and then explained why you may not even if the "why" sounded like a perfect fit. You came up with a list of bad fits just fine based on what they told you it was good at, without them having to spell out every no-go. Their list of reasons why not is intended to disuade people who would otherwise be their target audience.
As an example from someone who finds the language compelling in some ways, outright ruling out DSLs is a major factor that would rule it out of consideration for me. Better that they saved me the trouble of wondering!
What they wrote was (summarizing) that there is not a lot of tooling available, there still isn't API stability, and not many libraries available.