Probably all are true to varying degrees.

There was already an issue with sand smuggling and sand theft before the AI chip buyouts. Sand is the source for the silicon that gets made into wafers. There is a limited amount of input to produce silicon wafers, and increasing scarcity (and the supply purchasing competes on the market with concrete manufacturers and glass makers, among other industries).

Chip fabrication (lithography) machines can cut any pattern into the surface of a wafer (within the limits of their resolution). Changing the pattern to make a different circuit on the wafer is not very complicated. More complicated would be shifting the supply lines for peripheral components to produce SD card circuit boards vs whatever boards the DRAM chips are being assembled on - but as I understand it the major issue is that the AI companies have bought out the chip fabrication for future production runs (for the chips, not actual completed circuit boards) so the supply line part may not be relevant to the price increases. The issue is that all the chip foundries are making DRAM for AI contracts and not much else, so there is a shortage of other types of chips.

And at the same time, there is greed. As prices rise in some areas of the electronics market, suppliers see an opportunity to raise their prices even if their products are not directly impacted by the shortages.

I suspect that a lot of electronics manufacturers have been wanting to increase their prices for awhile, but the market was largely settled on the prices of things and no one could raise their price too high without losing a lot of sales. The disruption has removed the equilibrium, costs are no longer stable, companies are taking risks with high bids and still having no trouble finding buyers, prices are moving all over the place. There's fortunes to be made and blood in the water. Consumer electronics are the lowest priority for every manufacturer at every level of the process.