I think this whole system is kind of fucked up. Not just noncitizens in Estonia, that's only the tip of the iceberg. Every country in the world has some guest workers etc who are not citizens. The country benefits from their work and their tax money, but doesn't give them political representation in how their tax money should be spent, how their work should be regulated and so on. So non-citizens everywhere end up disadvantaged and poorer than citizens.

Americans fighting for independence had a good phrase "no taxation without representation". Today they don't apply this phrase to H-1B visa holders of course. But it's interesting to think about a world where this phrase was actually applied. Where every country would give full political representation to everyone living there, no matter what language or customs they have. You're here => you're affected by political decisions here => you must have the right to affect political decisions here, end of story. Or if you don't want someone having a voice in your country, then don't invite them in.