They are literally surrounded by countries that are strongly against new EU/NATO country in the region, have much stronger armies, are not shy to use those and can't be pushed politically or economically.
Before this whole euro integration process started they had good relations with half of these countries who also are still their main economic partners. The other half thinks Armenia shouldn't exist and are actively working in that direction.
So I don't think there's that level of delusion possible for Pashinyan to honestly think that is good and realistic move, he's probably being paid for this.