Belgium here.
I had a couple major health issues last year, and most of my medical expenses were extensively covered by healthcare. I still ended up staying home for about 5 months.
I work in a public service with an incredibly complicated structure, and there were a lot of miscommunications between the HR department and the health insurance company, which led to the both of them billing me thousands of euros (up to 4k from my employer).
Having troubles with the bureaucracy is obviously pretty standard in a welfare state, and debts this huge for a young adult are pretty scary, but after clearing everything up I'm at peace with this system.
The belgian (common) health insurance is backed by public funds and is mandatory, it is however different from the NHS system, as you get refunded at least partially from most private medical practices. It works pretty well, and the poorest can get a medical appointment from a general practitioner for 2 euros if needed.
The delays for non urgent optics, radiology and a few other stuff can be up to 3-6 months though, but there are a few ways to speed things up with the backup of your doctor.
