I wonder how much shared hosting is there really left, I imagine much of it move to VPS or cheap cloud boxes.

I highly doubt that. It's giant market and with these custom small sites made by third parties you actually want to have client owned hosting and third parties who deploy to that hosting. Clients have learned to separate these otherwise the third party can have huge leverage (your business and all data is ours).

I'm especially curious how much small-scale shared hosting is left. The big companies like EIG are certainly still around, but the little one-off hosting companies are much less common.

There's still a very big market of people for whom being given a VPS with ssh access and a command line is beyond their technical capability or comfort level.

Ever seen the upsell offers in the check-out workflow for hosting packages that come when you buy a new .com domain from any major registrar? All those are shared hosting packages where everything is done through some sort of web gui.

But you have to keep a VPS updated yourself, right? A hosted site doesn't require any action from the customer to stay up to date.