For me it comes to an almost philosophical question: do you want to live like an average person in a developed country, or do you want to live better than average in a different place with a cheaper cost of living?
Thank you for the calc though, seems really helpful.
This salary calculator is extremely accurate https://www.brutto-netto-rechner.info/gehalt/gross_net_calcu...
In any case, I agree with your overall statement: even if 86K/year puts you in the top 10% of earners in Germany, in reality it's hard to afford a decent house (not flat) with that salary (unless you wanna work until you're 67...)