There is an incentive for now. When the current supply shock goes away, the old market pressures will reassert themselves, and those companies whose supply chains are narrowly focused on the lowest-cost/highest-quality producers at the expense of diversification will outcompete those whose supply chains are diversified.
The parent questioner is asking, in essence, how can we turn this incentive from a one-time shock into a continued incentive to maintain diversification? As it currently stands shocks are far too unpredictable and episodic to serve as a market incentive. In practice, people don't diversify unless there's a constant and ongoing pressure for them to do so. It's much easier and cheaper to find a good supplier and rely on them as much as possible.
Today the supplier can not only sell to the company but to the consumers directly significantly cutting company's ability to level the price so the company is forced to drop the more expensive suppliers
We don't generally make our roofs asteroid impact proof, either.