Not English or a FPTP system citizen either, I'm afraid. If it is any consolation, we have elected unfit leaders using a ranked voting system too. It's part of the reason I advocate for multiple-front approaches to social betterment - all parts of all systems can be compromised by bad actors.
I'm also I'm not familiar enough with how Finland's election system works to make a direct comparison there, I only have experience in public education policy, not electoral systems.