Strengthening borders is the right move for European countries neighboring Russia, as Putin's hybrid war against the West is abominably using illegal migrants as pawns to destabilize and pressure Europe. As Finland follows the path of other nations, it’s likely to achieve the same positive results even if Kremlin-backed forces keep trying to force migrants across the border.
"Building walls" is an inhuman solution to migration. Moscow can then even claim the moral high ground by blaming the EU once these barriers are constructed. If this is truly an ideological battle between Russia and the West, then European nations and institutions must better demonstrate sound ethics when considering how to handle immigration and refugee flows.
There's an 80% chance that Finland will join NATO before 2024, according to the Metaculus prediction community.