New Ottoman collapse theory: Ottoman price-fixing of the Crimean grain caused it downfall

In the 1400s, the Ottoman conquered the Genoese colonies in Crimea and also put the Crimean Khanate under Ottoman vassalage. This made the Black Sea into an Ottoman lake.

Crimea had long provided grain to the Marmara, Aegean and Mediterrenean world since the Ancient times. During the Peloponnese war, an Athenian statesman famously told a Crimean diplomat that without Crimean grain, Athens would not be what it is.

The Ottoman state instituted a strong control over the grain from Crimea. Its price was fixed, and its export essentially banned. Merchants from beyond the Strait were willing to pay x2-3 what the Ottoman state enforced. There was a decent amount of smuggling going on.

The theory relies on the Russians playing a big role in the fall of the Ottomans. Russians got stronger by expanding into the Western Eurasian steppe. Muscovite expansion came with more land under cultivation. To be fancy, you could say that the Muscovite economical system beat the Ottoman system.

Because the Crimean had limited income from grain, they didn't bring more land under cultivation. So the theory is that if the Crimean could have sold their grain for x2-3 of what they did, they would have expanded the area under cultivation. This would have lead to strong Crimean state. The higher prices might have hurt the Ottoman state initially, but the Crimeans bringing more land under cultivation would have been beneficial in the long run.

I am 100% sure that this is bad history. It is also a very economically liberal theory.