> If you're thinking about designing a language, study as many other languages as you can so that you get a better sense for the design choices involved and how various concepts fit together.

I've written C, C++, Python, Ruby, Lua, Bash, POSIX sh, C#, Java, JavaScript, Common Lisp, Racket, Haskell, bc, dc, Zig, BASIC, Tcl, and some others I'm probably forgetting, and I've studied Rust, D, Ada, Idris, Coq, Isabelle/HOL, HAL/S, OpenGL shaders, Cilk, Cyclone, Ceylon, Scala, Clojure, Kotlin, F#, Scheme Lisp, Jai, Julia, Perl, Nim, and probably even more that I am forgetting.

Does all of that count? :)

> Ask people experienced with those languages what they like / dislike about them. Write something challenging enough to get a first hand understanding of some of those pros and cons. If you push on with your own language, this will help your efforts significantly.

Yes, I agree. And I have done all of that.

> If you get lucky, you might find a language that stops your descent into the rabbit hole.

"Lucky" is the operative word. Unfortunately, I'm picky and haven't been that lucky.