Unsatisfied with the solutions presented here so far, I released the python. She was effective. This solution doesn't require setuid permissions or any actually-insane monkey-patching with shared libraries and `LD_LIBRARY_PATH`. Save this script somewhere in your `PATH`. Don't forget to `chmod +x` it. Suppose you save this script as `pty`.

 #!/usr/bin/env python

 from sys import argv
 import os

 # I've had problems with python's File objects at this low a level, so
 # we're going to use integers to specify all files in this script.
 stdin = 0
 stdout = 1
 stderr = 2

 if len(argv) < 2:
 os.write(stderr,
 b"""A tragically beautiful piece of hackery, made to fool programs like ls,
 grep, rg, and fd into thinking they're actually connected to a terminal.
 Its usage:

 pty command [arg1 arg2 ...]

 Examples:
 pty ls --color -R | less -r
 git log -p | pty rg <search terms> | less -r
 """)
 exit(255)

 # We do not use forkpty here because it would block ^Cs from reaching the
 # child process. And we don't need that.
 ptm, pts = os.openpty()
 pid = os.fork()
 if pid == 0:
 # The child runs this.
 # To get the behaviour we want, we only need to replace the process's
 # stdout with pts. Everything else should remain in place, so that things
 # like `ps -eF | pty rg python | less -r` will still work as intended.
 os.dup2(pts, stdout)
 # This is not like a subprocess.call(). It replaces the entire child
 # process with argv[1:], meaning execvp will not return! Web search
 # "fork exec" for more.
 os.execvp(argv[1], argv[1:])

 # The parent runs this.
 # If the parent doesn't close the slave end, the script won't be able to
 # exit. The next read on ptm after the child process terminates would hang
 # forever because pts would technically still be open.
 os.close(pts)
 while True:
 try:
 chunk = os.read(ptm, 4096)
 except OSError:
 wait_pid, status = os.waitpid(pid, 0)
 exit(status >> 8)
 os.write(stdout, chunk)