I'll never claim to be an econimics expert of any sort, but I do know how OEMs and hardware manufacturers work together and this situation is unlikely to change the way their partnerships have been built over the years.

When any manufacturer has the capacity to produce X pieces of product to be sold to a number of OEMs, the OEMs that will make the biggest orders will negotiate the best prices. That has always been and will probably always be the case.

Microsoft's mandate will cause a spike in OEMs' SSD demand for a number of months, yes. Maybe even a year or so. Suddenly all OEMs will be asking for more SSDs than ever before.

Manufacturers already have long-standing business partnerships with many of those OEMs, though, so it's unlikely they'll jeopardize those partnerships by blackmailing OEMs into buying SSDs at high prices, especially those that will make big orders.

Some OEMs, the smaller ones, will not be in the same advantageous position. But those did not sell HDD-based PCs in volume anyway. In a sense this is all about the transition of the cheapest mainstream PCs big OEMs currently sell to SSD. That is all.

You can also be sure that, as we are discussing this, SSD manufacturers as well as OEMs are already planning on how to handle the spike in demand caused by Microsoft's mandate. Those companies will not ruin their business relationships over a short spike in demand of a specific component. They will find a way to go through that together and OEM SSD prices will normalize after a time.

That is a much more likely scenario than seeing e.g. the cheapest HDD-based PC suddenly costing much more than before just because OEMs dropped an SSD in those. Just my two cents.