If it's useful, I looked into this a little with a Trixie podman container (from a Bookworm host). With just libedit installed, I got (having previously done ,input readline):
root@04bc7ba8ba59:/racket# ./bin/racket
Welcome to Racket v8.9 [cs].
; Warning: no readline support (invalid memory reference. Some debugging context lost)
>
I then did raco pkg install readline-gpl and apt install libreadline8, which got me to a worse state:
root@04bc7ba8ba59:/racket# ./bin/racket
Welcome to Racket v8.9 [cs].
invalid memory reference. Some debugging context lost
^C; user break [,bt for context]
^C; user break [,bt for context]
^C; user break [,bt for context]
,q
^[^[^[
^C; user break [,bt for context]
^C; user break [,bt for context]
^C; user break [,bt for context]
(And Ctrl-D didn't get me out of this.)
I'd thought about trying racket-x86_64-linux-natipkg-3 because the Mac equivalents include libedit, but it looks like the Linux ones do not, and I definitely never advocate adding more to those packages other than as a last resort.
FWIW, on Bookworm I get Racket by:
sudo apt install guix
guix pull
guix install racket
(I maintain the Guix packaging of Racket.) We also have racket-minimal, zuo, and chez-scheme-for-racket (in addition to upstream chez-scheme) packaged.
I also expect, now that Bookworm has been released, David will probably update Racket in Debian testing soon, though if I were him I'd wait until after the imminent Racket 8.10 release. Generally he keeps the packaging in testing and backports very up-to-date. Sometimes he's landed updates in Debian before I;ve gotten them into Guix, even though Guix has a rolling release model.
I don't have a principled answer, but, tangentially, this reminded me that I'd found in Native library problem on package-build service · Issue #2 · libgit2-racket/libgit2 · GitHub that your mflatt/pkg-build-deps-min Docker image is still based on Ubuntu 16.04 Xenial, which is getting to be quite old indeed. At least when I wrote my related notes, the Racket releases were building on the slightly newer Debian 9 Stretch (June 2017), which has been out of LTS support for a year and is only covered by the even-more-limited ELTS.
I saw in What is the Racket roadmap? - #6 by mflatt that you are planning to look at the racket/draw native libraries relatively soon. I don't have it all paged in, but I know I've had or heard about various issues and ideas at least somewhat related to native libraries; I can try to make a list relatively soon if something like that might be useful.