FreeDOS is technically a modern, actively-supported DOS.

With the ease and speed of browser-based DOSBox (look at internet archive), DOS becomes a highly portable target for small games and even non-trivial games.

Anything up to the complexity of mid-90s AAA titles can run practically anywhere with a keyboard and mouse.

Games like Tomb Raider, Command & Conquer, Quake, etc. This is pretty compelling if you want a "it just works" platform.

Having SDL now makes that even easier.

SDL is a cross-platform multimedia library, and DOS is a platform.

So I can play Dota 2 on DOS.