It might just be a big power grab. As soon as Xi got his third term he announced that he was going to expand the number of state run enterprises and he more than doubled the number of members on his executive decision board
Putin surrounded himself with yes men, and you have to imagine that was a factor in his decision to invade Ukraine. The new members of the decision board are all said to be Xi yes men.
In the last couple of months he has been able to significantly increase his hold on government; which is crazy given how much control he previously had. I don't know if there is a specific link to his covid policy and his ability to gain that control, but certainly all of the tactics and technology used to implement his covid policy would have been paramount in his ability to gain more and more power.