So, overall, these Stalin's occupation plans worked out just perfectly
Authoritarian regimes are partly at fault here.
If Latvia, Lithuania, Estonia, Poland, and Finland (and maybe some other central European countries too) had united in some kind of Central-North European Union - maybe history would have been different.
But authoritarian leaders at that time were too arrogant to agree on something like that - Ulmanis, for example, was not thinking about foreign relations at all.
Latvia was a "neutral country" at that time - LOL.
At least our politicians have learned of his mistakes - and that's why we are in the EU and NATO now.
The fact that Lithuania and Poland did not have diplomatic relations was a biiig mistake.
Lithuania got Vilnius back, but with that came 50 year long occupation.
Well I am trying to be understanding about why the Baltics are choosing to discriminate against Russian speakers
As I said - the fact that some employers can refuse to speak Latvian proves that Russians are not the ones discriminated here.

And in Lithuania there are no such thing as non-citizens.