That will be a huge betrayal of all pro-Russian people in the "new regions of Russia". It will be the end of popular support Putin enjoyed over all the years of his rule.
Withdrawing from Kherson was hugely unpopular measure and over hundred of thousand of pro-Russian civilians left Kherson[0] along with Russian army because they were terrified of what the revenge of Ukrainian regime would be.
That was nearly four years ago. Russia has lost a lot prosecuting this war since then: lives, money, infrastructure. Reports are that Putin is already losing support over it.
I have no idea whether that has changed his mind about anything. I don't give a lot of credence to anything he says.
I hope he's right, and this war will end soon. If that costs him popular support, I won't be sad about that. If he manages to retain office, I won't be thrilled, but it's better than ongoing war. This war is a pure loss for all sides, with absolutely nothing to be gained. It persists solely to avoid even greater loss from surrendering.
"Russia's stagnating battlefield performance is placing the Kremlin in a worse position to extract major political concessions." -- Institute for the Study of War
Putin sees what Trump is doing with Iran (i.e. the communication strategy based on confusion unto contradiction) and how well it is working: worth a try!