I think that things like wanting to celebrate a country and acknowledgement and a day of mourning and acknowledgement of the horrors that happen to indigenous people can both happen in parallel.

Honestly, if it's intended to be a day about celebration for the history of a country it'd be cool if in the future people could celebrate the reparations and acknowledgement that have been made since now. It's like the saying goes, the best time to plant a tree was yesterday and the second best time is today. So a movement like this is good because in the future it'll be another thing to celebrate for your country.

On a related tangent, you guys could get another holiday specifically for remembrance of the lives lost from colonialism and get another holiday! Canada did it a few years back and now they only have 2 months with out a federal holiday.

Edit: For context, this is coming from the perspective of a Canadian, and our founding fucked over the indigenous pretty badly here well up until current day, but super fucked them up until like as late as the 1990s, so that's where I'm coming from with my feelings and thoughts.