Just have to say. I've been writing and publishing on the web for more than 20 years now. I've had a couple of high-traffic posts, been slashdotted (once), and was once featured in a blog post on The Atlantic. I had a podcast for four years with a moderate number of subscribers. All of this was self-hosted. I have NEVER had to worry about bandwidth costs. The bandwidth included with the hosting/VPS plans I've used over the years has always been more than sufficient.
This makes me think that bandwidth 'insurance' plans should be a thing. Pay a nominal cost each month to ensure that if something on your site becomes a massive viral hit you get a few weeks of bandwidth cost defrayment to weather the storm and allow you to find a longer term solution if needed.
Really? It makes me think the opposite. Supposing I had ever bought such a policy, 100% of its cost would have been a complete waste, despite having some extremely high-traffic hits.
But all that aside, this product exists already, it's called a CDN.
Not a bad idea in general, but very risky as an independent business because web hosts can just offer it as a freebie or add-on the moment it starts catching steam with customers. They often already do, although they don't say so or commit to it.
> I have NEVER had to worry about bandwidth costs.
Well obviously you aren't using the right JS framework then. Modern technology will fix this problem for you. Especially if your pages are loading too fast.