Since you obvious don't know what unix philosophy is, it's a md writer..that's it, you want to convert it..take a converter like pandoc. If you really think every writing program should have it's own converters..well then you end up with less interchangeable stuff. One tool for Writing another one for conversion..is that so complicated?
Has nothing todo with programming, a real hammer is better as the backside of an axe. A Specialized Knife is better then a Swiss-Pocket Knife. One tool for one job but make that job perfect.
Ever see a framer’s axe? It’s one part axe, one part hammer. It’s perfect for framers - they love it. It’s one tool which lets them chop, modify, remove nails, hammer in nails, whatever they need to do, without having to carry 4-5 different tools.
The idea that a specialized tool is always better than a multi-tasking tool is simply not true. One must only look at the popularity and utility of leatherman multi-tools to see this to be true.
Even in programming circles, one needs only to look at how many options there are for ‘ls’ to see that “one tool for one purpose” is not always the best thing.
If you have an editor, you need two way communication -- they are going to make changes in your word document, using track changes, so you also need to be able to convert back.