Also, you seems to underestimate how bad the weather in Amsterdam is. Cycling on a bridge through rain against the wind at 5 degrees (C) isn't very fun either.
When I lived in a more hotter climate, 30ish (C) was a-okay for some people to cycle to work and then get a shower at work. It's all about infrastructure really --- be it showers, speed limits or bike paths.
Besides I am not sure if you are willing to drop 7.50 EUR per hour for parking in the center. Most companies in Amsterdam have none or only limited spots for parking anyway.
My solution was move to a small town where it’s easy to drive to work. Getting around in large dense cities sucks no matter how you do it.
If one needs excuses to justify having a car and being stuck in traffic, hills ain't a valid one. 30km/h is great, makes for less noise, less air pollution, and now we see, it makes it for 0 traffic deaths. Much better to have the option to reach a grocery store on foot, by bike, by public transport and car than have no options but a car. That makes for less cars on the road, and, funnily enough, 30km/h on a non-busy road will often get you faster to where you want to go than 50 on a busy one.
Again, that's why we Europeans are both happier and fitter than our American counterparts.