Really depends on the type of job. Software? You are making bank in the US and partly because companies in the US can move quick because of their labor laws.

No, that's not true. Most companies offer at least HDHP plans either fully covered or at minimal cost. HDHP plans, by nature, have high deductibles and out-of-pocket maximums, but usually well under $10k per year. So for a typical case, unless there's some catastrophic expense not covered by any insurance, the difference can't be more than $10k per year. The difference between typical compensation for a seasoned SW engineer is much more than that, even before taking options & stock into account. In the US $150-200k is pretty common for a seasoned engineer. In Belgium, you'd look at around E100-110k from what I could find online. And I don't think Belgium has lower tax burden overall. So the health insurance alone doesn't come close to covering the gap.