The newer OS are actually the graphical improvement of the older ones. I don't think anybody would be using DOS or BASIC unless for the specific fields that has been using it. i.e. no personal computer in the world would be a DOS or BASIC. It would be possible to make crypto work in a DOS computer that's on modern hardware but it won't run on a 44mb disk.
Limited storage space is a huge limitation for running crypto on older systems. I've figured that it wouldn't be feasible to develop a cryptocurrency with old programming languages on old operating systems. Crypto hashing algorithms require some processing power which could make a developer's life impossible with low-end CPUs. Imagine running a Blockchain network on a single-core CPU with very low RAM, small storage space, and a slow data-transfer rate. It'll take months or even years to design a cryptocurrency of a large scale like Bitcoin on it.
I'll be surprised to see someone design a cryptocurrency on a system which uses outdated operating systems like MS-DOS, Windows 95, or Windows ME with very limited hardware requirements. It's not impossible to do it, but not entirely feasible for today's standards. People from third-world countries would be forced to get a modern system (either a PC or mobile device) just to get access to crypto. As long as anyone will be able to use crypto in the most affordable way possible, nothing else matters. Just my opinion
