The way I understood it: Doing both the Olympics and Worlds meant that he had to stay in peak form from July through October–basically, he had to be there from the beginning of Olympic selection in early July and maintain it until the end of October.
He then had four months from the end of Worlds to Winter Cup, where he absolutely had to qualify for National Team to keep getting a paycheck and be able to afford continuing to do gymnastics. His living costs, health insurance, and training costs depend on it. Most people would have been working upgrades in the periods between Olympics and probably November or so, when they started really working routines for Winter Cup. He didn’t have that time–he needs upgrades, especially on bars, but he didn’t really have time to work on them and get them routine consistent or get out of routine shape and back again in the time he had. Add on to this he’d already been pushing at peak form for over three months and was absolutely exhausted.
There simply wasn’t the time for him to take any real break the way most athletes would after the Olympics and Worlds for basic recovery, much less work upgrades and get them consistent. If having competed at Worlds and Olympics assured him of a NT spot until the summer, he could have used his time better, rested, gotten upgrades in shape, and probably showed up at Winter Cup with a couple of routines so they could verify he was still actively training and deserved his stipend. Instead, he had to be all-around ready and there simply wasn’t time to rest and/or upgrade–he just had to keep grinding.