My very late contribution: I'm playing this classic game on new hardware (Windows 11) which, in my case, automatically defaults to widescreen mode on my TV/monitor. But I had the
opposite problem -- I actually prefer the original aspect ratio, which keeps good crisp text, and I had to find a way to get it back.
My fix (to return it to the original aspect ratio) was to instruct my computer graphics card to 'center' the image on my widescreen TV. I have an AMD card, and the centering function is found under GPU Scaling. Other graphics cards may have different means of doing it, so here's a link that might help :
https://www.pcmag.com/how-to/how-to-get ... d-pc-games
If you want the game in full widescreen on your hardware, but you're not getting it, you might be able to fix it by adjusting your graphics card as well.
Hope this helps!
RJinVA