"be very prepared to survive in the scorching sun and dust in the desert for days without any option to resupply food and water"

I have done Central Asia from Europe to China by bike twice, most recently 2024. Absolutely no problem with resupplying food and water daily. There are food stops and railway-worker infrastructure in the Kazakh and Uzbek deserts. And while Tajikistan and Kyrgyzstan have a lot of wild mountain beauty, they are still inhabited. Indeed, local families earn some money by catering to cyclists.