It's not relevant to Soviet coins, no: it's a very rudimentary form of what's known as a land acknowledgement, which is something a lot of Native activists in the USA, Canada, Australia, etc recommend that people should do while living in or visiting these regions. It's not a practice without controversy, however, mainly because institutions of power are constantly trying to co-opt this practice and turn it into a sort of "ritualized crocodile tears" to exorcise guilt, or even into a sort of "bragging between the lines".

Once I'm back home — where I at least know the land wasn't violently swindled from anyone — I'll stop doing the land acknowledgements, but certainly will continue to push for solidary action with the Dakota in my org, and continue with individual actions towards restoring Dakota sovereignty.