Sure, but the Thirty Years War was no joke either. I'm not sure that you're making arguments any more. You may be right that borders cause more harm than good, but the bulk of historical evidence is against you. If you're going to challenge the principle of Westphalian Sovereignty[1] then I think you owe more to a good faith discussion of the topic than a glib remark about German history. Assuming for a moment that you're talking about WWII, then I would cite that as a case in favour of my argument not against it.
Westphalia is a blip in history. The world has gone through cycles of war and peace, borders or no.
Meanwhile, there are more separatist groups than there are countries, and some of them enjoy blowing things up. How did borders work out for the Middle East? How did they work out when the USSR disbanded? Etc etc.
[1]https://en.wikipedia.org/wiki/Westphalian_sovereignty