As far as I know, the sofware font loaded as a TSR was only required when a code page other than 437 (US) is required. We always need to load them for example, since several of Turkish alphabet characters (i.e. http://en.wikipedia.org/wiki/%C4%9E) was not covered by 437 and/or 850.

Untill MS-DOS 6.xx, it was not even possible without a third party TSR, since code page 857 (TR) only included with that version and above.

IBM PC-DOS had Turkish code pages long before MS-DOS if I remember correctly.

Yeap, we had the same issue with Greek language on ms-dos. I remember 2 possible solutions, one using software and one involving hardware changes. In both cases I think the target was to replace the extended ASCII table, with the characters needed for displaying the language correctly. Using software there were some TSR programs that did that. The other way was to use a modified bios on the vga card. I still have a couple of old vga cards with "Greek support", and one easy way to tell it's like that is to check the system configuration table after the post. The floppy drive would be listed as "3υ" instead of 3½, as the Greek letter υ replaces ½.

Exactly the same problem with our Ç,Ü,Ö, S with cedilla and soft G, but we never had VGA cards with altered ROMs. So "vgatrk.exe" was a must in every autoexec.bat file... 🤣