This assumes that because it was viable in the past, it must be viable today. Maybe ads had more revenue then, but times and people change, and now ads aren't that lucrative anymore. One needs to factor this in the decision to continue hosting a blog or whatever else. This trend was forseeable. On a personal note, this is good. Ads are either annyoing or outright dangerous. So the less, the better.
If you want to host your blog, then just pay for it. I do the same. Not because I want to earn money with it, but because I want to. I can see why this is a problem for commercial entities, but not for personal stuff.