The problem is not the existance of non-Orthodox religions in Russia. No one is closing Roman Cathlic churches or sinagogues, or mosques there.
The core of the problem lies in the attempt to "evangelize" Russian Orthodox population! That, in effect, is telling the Russian Orthodox that they are not Christian!.
One must seriously question the motives of those who are "evangelizing" (i.e. "converting to Christianity") people who have been Christians for more than a millenium.
Given the vast multititudes of humanity who have not been baptized, the Western evangelists of all denominations must have their priorities mixed up in addition to denying one of the most Christian people their own Christianity.
We are not even talking some peripheral off-shoots of Christianity that deny Trinity, but truly orthodox followers of the teachings of the Fathers of the Church, a church with valid priesthood and Apostolic authority shared with the Roman Catholic Church, a faith with the same number of Sacraments, and Eucharistic litrurgy.
It is really sad that a church, whose membership outnumbers the Orthodox Christian faithful at least fourfold, finds it necessary to alienate, insult and politicize a church that is in every way its closest and valid relative, simply because it justifiably rejects papacy and the notion that the early Church was anything like the pope-dominated present one. That hardly seems like a valid priority for anyone interested in evalngelizing the world.