Putin has sorely miscalculated with this invasion. Western nations have shown exceptional resilience and solidarity in response to Russia's assault on democracy and the geopolitical power balance in Europe. It is very unlikely the Kremlin will retaliate against Finland and Sweden joining NATO, especially as it's reckless attack on Ukraine has decimated its military resources.
Sweden and Finland's decision to join NATO wouldn't be without risks. Despite the rapid evolution of public opinion there isn't clear majority support for the move in either nation and even an immediate application could take months to process, leaving them vulnerable to a strike by an enraged Vladimir Putin.
There is a 14% chance that Putin and Zelenskyy will meet to discuss the peaceful resolution of the Russian-Ukraine conflict before 2023, according to the Metaculus prediction community.