Wait, if the default -:t setting could be changed from "1"("A"?) to "8" with the motivation that that would make it friendlier out of the box,
what would the implied worst-case be, for instance on a 0..255 only terminal?
So the -:t setting affects both console IO (print read-line etc.) and REPL IO (the Read step).
( I guess the implied worst-case for the current "1"("A"?) default is
* If the terminal is UTF-8 only: Trashing of input of >=128 characters, e.g.
gsi
(string->list "ü")
(#\xc3 #\xbc)
(REPL left-right input behavior when attempting to input them is messed up but that could maybe be fixed.
Non-escaped output of the trashed input has an "untrashing" effect which can conceal the trashing problem, but that is intended, as in that the ISO-8859-1(&ASCII?) coder has a 1:1 byte to char mapping, and also showing the same with escaped output immediately shows the problem e.g. "\303\274" for what should have been "\374".)
* Scary error messages when trying to output unicode chars
(print (make-string 1 (integer->char 1234)) "\n")
*** ERROR IN ##write-substring -- Can't convert to C ISO-8859-1-string (write-char #\u04d2 '#<input-output-port #2 (console)>) 1>
)