You're wrong on every count about my experience. And once again, please: I'm just saying that stages in Read-Eval-Print-Loop does have differences in homoiconic and non-homoiconic languages. THAT'S ALL I SAID. There's zero controversial taste in that statement. None. I'm not bashing on Ruby, or Python, or any language you favor. I'm not telling you to use this or that. I'm just pointing out at specific differences that exist.
So if you implement a non-homoiconic language in SBCL or Racket does the REPL blow up? Is Rhombus language a psy-op?
Implementing C-like language in Lisp runtime - your interpreter reads C-like source, parses it to your own AST structs, and evaluates those. The host being homoiconic says nothing about the guest. You would have to write a guest REPL anyway (if you want one).
Rhombus built on Racket, yes, means it reuses Racket's machinery: the macro expander, the module system, the compiler, the runtime. But it doesn't mean it inherits Racket's parenthesized syntax.
Racket's expander does not operate on text. It operates on syntax objects (shrubbery). It has its own REPL, because the Read stage has to parse shrubbery syntax, not s-expressions. So, my original point stands - REPLs do have differences for homo and and non-homoiconic PLs.