Well PyonR is not a replacement for Racket. It's something totally a different project altogether. Rhombus is supposed to replace Racket. We could have PerlRacket or AwkRacket or RubyRacket and none of it should effect Racket, because you are using Racket as a language to build things, not exactly using RubyRacket as a replacement for Racket.
This is how it rings to my ear. Racket as is, is in some way frozen when it comes to features and big changes. Rhombus is where the next set of awesomeness will happen. Lispers who happen to be core users of Racket have no use at the time for non-existent Rhombus, and its not Lispy so their whole use case ends here. Racket won't be continued to developed in the same breath as Rhombus, so Racket is also dead here. C based language devs have a lot of good stuff already, so they don't need Rhombus either.
Eventually this could lead to the exact situation Perl was in the 2000s. The core development was frozen for 5+ years. The language usability just fell year over year. Perl 6 took forever to even start with the implementations. Pugs, then Neitza, then Rakudo. Eventually they came to a point, where they announced Perl 5 development would just run parallel as a separate project compared to Perl 6. By then a lot of dev mind share was lost to Python/Java. Now neither Perl 5 nor Perl 6 have significant mind share. Perl 5 certainly has lost a lot of its users.
Also in general trying to be everything to everybody is a bad idea in general. Ask Parrot VM people. It doesn't work the way you expect. You won't solve anyone's specific problem, and it takes forever to get done.