Besides, 90K after taxes is upper middle class. 160K / year is 13K / month which is nearly twice the average income of the richest country in Europe (Switzerland) (https://en.wikipedia.org/wiki/List_of_European_countries_by_...), or top 0.1% according to https://www.givingwhatwecan.org/how-rich-am-i.
And that's just salary based on that number, it doesn't include other income sources.
Also there are usually very very generous pension schemes here, so total pay is actually quite a lot higher than stated. In addition there is very generous holiday allowance, 41 days at UCL for instance, since you get extra holidays when the university is closed over certain holiday days.
I don't know what their salaries would be exactly. This is probably most dependent on where they land, as salaries are very often standardized in Europe. There's usually salary grids per institution dependent on seniority with some milestones being merit-based. Quick google search indicates gross salaries for Professor level (mid/late career) researchers to be around 110-165k€ in NL.
That seems pretty sweet. It's comparable to what US professors make in the hard sciences, as far as I know, with lower CoL than most areas where professors make similar salaries.
And again, salary isn't everything to a researcher. If they can't hire, they're pretty strapped. At this career stage, they're managers, not so much individual contributors. I'd say a maxed out lab for 5 years off the bat is pretty enticing, which also gives time to get up to speed on European funding schemes like ERC grants.
I was a postdoc in the US during Trump's reelection and there were several months where my institution and others had completely cut off scientific staff (such as postdocs, research scientists and engineers) recruitment due to NSF defunding and other threats. Even now, they got taxed on endowment and lost basically 10% budget. This is considerable, and a source of stress for researchers and their current/prospective staff. You can't work properly if you're under the Damocles sword of being laid off / having to lay off your staff.