While I understand this sentiment - especially since as you say, most (if not all) of today's accepted states and borders are the result of bloody, unfair conquest - I do personally struggle with a system of objection/dismissal based on the "well, it's a dog-eats-world" mindset. Interestingly, I've also found that many people (I'm being a bit hand-wavy here, I know) who are completely fine with dismissing indigenous land acknowledgements have plenty to say about Tibet re: China, or Crimea re: Russia, etc. Perhaps it's all realpolitik posturing, but if it has been I certainly haven't been able to tell.

Seems to me that so long as the peoples who "lost" in history are still around and able to generate sympathy, empathy, and understanding, it lands upon us to seriously think about whether or not we should continue the status quo and carry history into the present.