and people who speak only Russian and were born and lived there for 50 years have lost rights (became non-citizens) from this day ever after.
Please look some posts above - I already said that people who were citizens of Latvia and their descendants before 1940 did not lose anything - they regained their citizenship regardless of nationality, language skills, etc...
Non-citizens have no citizenship - because state (USSR) that gave it to them does not exist anymore - they have never been Latvian citizens.
Everyone lost their USSR citizenship - me included.

I think it is surprising though, that nobody in the EU has complained about it
EU and most of western countries always have stated that Soviet occupation was illegal. Therefore everyone that immigrated here during Soviet occupation is an illegal immigrant.
And since Latvia restored citizenship to everyone that was its citizen before occupation - everything is OK according to international laws.
And more - according to international laws - Latvia has rights to deport Soviet immigrants (like every illegal immigrant) - but we did not do that and never will - we want them to naturalize, learn Latvian and become Latvian citizens.