Use the best tool for the task. markdown is really good for talking to AI as a human for example.
Same goes for JSON, YAML, etc.. use what makes sense to you. I like markdown but I have issues with it as well. I like html, but i despise it sometimes. One-size-fits-all is the real enemy.
My view is that for all *langs (markdown, config, data, code, styling,etc..) we should leave the proverbial cave and come down from the trees, and talk about interoperability and best practices. Contracts, expectations, and exceptions.
There is this pattern where we invest in some software technology, and it becomes this ideology people fight over. Or invest a lot into it and fall into sunken-cost thinking.
Being able to rapidly figure out the best tool/solution, and readily tear out the old and patch in the new with minimal loss and friction, that should be the next era of tech. Not a repeat of the old, with a slight twist. I don't need another JSON, Markdown, HTML, CSS, C, Rust,etc.. especially with the advent of LLMs (hype aside), syntax is important but it isn't what it used to be. I want to be able to write in Markdown and know that if there is a better format, I can easily stop using it and reliably transpile all my existing Markdown, and tooling that works with Markdown to use that new format.
Adaptability and communication are the biggest dead-weights holding back technological progress.