Most of these micro-SaaS are in shovels business if this was a new gold rush dream. I've observed this space for years, the only saas that makes money is marketing tools / analytics. It's true that B2B is boring, it does not have many types of app. I don't have number but my perception is that this long tail has a big chuck of shovels business. And I'm very skeptical about "niche" vertical type of app, I think it's tooooo small market share even if you told me that some market is really big that 1% is enough for small fish.