I think we directionally agree; about the post-Soviet phenomenon - I know for fact that this phenomenon started immediately after the war and was part of consolidating power by the Soviets. The communist Poland was, in a weird way, quite nationalistic. But you are right that this phenomenon has its reneissance, or even reinforced version now as we're speaking.
I don't fully understand what specifically do you mean by saying that there was no holocaust to non-Jewish Poles, but thousands of them died in concentration camps all around territories occupied by Germans and often shared identical fate to those who were of Jewish origin.
If I understood you correctly, you use term "holocaust" to describe mass extermination of Jews and Jews only, and as long as you acknowledge there's been other mass killings during the war, I'm completely fine with that.
e: it's not how I was taught history at school - e.g. teachers would include non-Jewish Poles, Russians, Hungarians, Romas, Sinti, and other nationalities that were sent to death camps too - I think by holocaust they basically meant death camps (regardless on who was killed in there) rather than the bigger scheme of killing all the Jews.