I think you're right but missing the context: badssl.com was setup as a resource for security engineers who are running tests. It's great for that and it allows the kind of fine-grained testing which anyone who is developing software, configuring firewalls or group policy, etc. would want — i.e. if you do anything which consumes HTTPS, why not take the time to add a step to your CI process which prevents accidental regressions?
The dashboard (https://badssl.com/dashboard/) is very new — see https://github.com/chromium/badssl.com/issues/257 — and as the person who opened that issue, my context was different: that conversation started among a group of U.S. federal government employees who are often in the situation of needing to use a MITM SSL proxy for compliance reasons and don't directly control it, often lacking even the ability to install software on their primary workstation (not without cause, given the threat model). Being able to run tests in a browser and send the helpdesk a single link saying “These three boxes should not be red, please file high-priority ticket with the network group” is really useful for getting changes through quickly.
I think https://badssl.com/dashboard/ does a good job at that — you could probably do something like what SSL Labs does with a letter grade but I think the Good/Okay/Bad levels is probably the level of nuance you want for a simple “Should I learn more about this?” prod.
What I'd like would be for that to eventually become the default view with an advanced tab for people who want to drill down into the full list of everything available.
If you see the dashboard things are clearer, but there's a mismatch between connected/not connected and what they were supposed to do.