I think it's more that there isn't a whole lot of commercial software of much import for the Model T, at least compared to a system like the Coco. What there is tends to be in ROM format or community freeware. The model T tended to be a fully portable, peripheral system to whatever main computer people had on their desk. So the fancier full featured software and games ran on the main system.
The built in ROM software is the main thing. Then the few, common option roms which you will find when you have a REX. The coco has a lot more commercial games and application software. As to freeware there is the club100 archive, the model 100 SIG archive and the club 100 personal libraries. There's web100 dedicated to the NEC machines. For documentation and some applications there's my Bitchin100 site and Brian White's Tandy wiki Or maybe I'm wrong and I just don't know how much commercial software there is because it hasn't been collected in one place. I guess if you find something advertised in Portable 100 issues that looks interesting to you, ask about it on the list and we'll see if we can find it. -- John.