>In NL, you pay ~€110/month annually, with a max out-of-pocket cost of €385 per year. So, maximum €1600 cost annually.
My provider, CZ, charges ~€150/month with max-out-of-pocket ~€385. If you get the full ~€850 out of pocket then your monthly payment drops to ~€110/month.
I would guess that you are also including "anvullende verzekeringen", additional cover for e.g. dental/glasses/physiotherapy etc in your premium, because if you check a price-comparison site [1], then the majority of insurance policies are in the €110 - €120 range.
The extra insurance (dental/glasses etc) is also a bit of a scam, because the amount covered is often less than or just equal to the premiums that you pay in a given year, and you'd need to also be buying a new pair of glasses every year, always visiting the dentist, and so on. It's probably more economical to simply pay these costs out of pocket.
My provider, CZ, charges ~€150/month with max-out-of-pocket ~€385. If you get the full ~€850 out of pocket then your monthly payment drops to ~€110/month.