Russia's unlawful invasion of Ukraine did not start in February 2022, but in 2014 when it illegally annexed the peninsula of Crimea. What started in that Ukrainian territory should end there; Kyiv has every right to try and regain the peninsula within its internationally recognized borders.
While Ukraine may have a legal and moral case for attempting to retake Crimea, strategically and politically, it's not a good idea. Following a year of war, Ukraine's forces are already heavily degraded and they may become too thinly stretched in attempting to take the peninsula that has been heavily fortified since being taken by Russia nearly a decade ago.
After the coup in Ukraine in 2014, protests against the putsch erupted in Crimea and its residents overwhelmingly voted to reunify with Russia through a referendum. Crimea is legally part of the Russian Federation and any attacks on it should be treated as attacks on Russian sovereignty.
There is a 1% chance that Ukraine will officially recognize a former Ukrainian territory (Luhansk, Donetsk or Crimea) as independent before 2024, according to the Metaculus prediction community.