the reality is, the netherlands is a right leaning country, look at the last election results.
A lot of people in the netherlands are very divided about poltics (stop the war, and side with the US, leave the EU, or give more money to ukraine and are pro EU). I hear about this on a daily basis at work. I am quite sick hearing about it. As a hiring manger at one of the big four banks in the netherlands, seeing something like the flags, is a obvious sign as to what side the OP leans towards. Having enough issues on my plate, and not needing another person to start a debate between team members at work is enough for me to stop, and not hire said person. The OP is or was a zzp'er (freelancer) in the netherlands. I think it's a little silly to limit your future contracts by brining in politics into tech. What's the purpose of having it there?