Putin’s approval rating is 80%. He has always paid close attention to his popularity.
At the same, Russia is entering the post-Putin era because he is a lamb duck and the Russian Constitution currently limits the President to two consecutive terms.
Nothing prevents him from changing the Constitution to eliminate term limits or to serve again as Prime Minister. He has plenty of time to decide on his options if he wants to remain in office after 2024.
The Presidential term limit in the Russian Constitution is nowhere near as strong as is our 22nd Amendment. It's basically meaningless as it only prevents serving a third consecutive term as President, as opposed to the 22nd Amendment's lifetime ban after two terms. Putin already showed this during his tenure as Prime Minister (i.e., de facto President).