The Guardian has an article on reasons why Russia might seek an end to the war. Most of the reasons are covered in @Cardigan 's OP, but there is another one that keeps cropping up: Ukraine has become a missile and drone superpower. They’ve been outsourcing their tech to the Middle East.
Russia has a huge shortage of labor (due to conscripts and emigrees) that it is marking bad inflation worse. And there are more reports of Russians speaking out against the war.
It could be that Russia feels the tide is turning and sues for peace this year.
There were reports last week that some EU countries are getting tired of the US’s progress on peace talks and are considering initiating their own. The rumors got shot down quickly; presumably that is a ways off.
FWIW, here is the old thread on Russia using nuclear weapons in Ukraine: