It is not new but as long as you can innovate and find a sweet spot, you might get a decent amount of money.
That aside, is radio still popular? And why does it have to be decentralized? I don't think it's an attractive idea. Instead of doing that, make a new platform that's similar to Patreon with Bitcoin.
mrquackquack
Am I the only one who found your posts a little bit difficult to understand?
Everything, blogging, forum, streaming and etc what you stated is popular, if not, at least has it's own huge customers. If you are great at something, then you'll have customers always, there is demand - there is supply.
You can create offshore cloud hosting or storage hosting and accept bitcoin deposits, this is the place where you'll mostly have users with wish to pay btc.
Do you want to create blog around bitcoin? For example there is one amazing blog: https://1stminingrig.com/ <-- See it, great option what kind of website to run and how to monetize.
There are a lot of website ideas but you have to choose niche where you'll be able to easily collect crypto community. Not something like streaming because it will take a lot of money and Vod also stated everything correctly.