It’s interesting that the focus is on porcelain as a cooking surface but misses the biggest reasons for it displacing engineered quartz or granite for countertops. There’s a few factors at play here leading to the prominence of porcelain.

For the induction cooktops, you can cut porcelain slabs to 6mm compared to your 3cm (sometimes 2cm) quartz and granite. This is also why you can use it for walls and floors. The thinner materials allow the magnets to actually function.

The manufacturing process for engineered quartz is now being interwoven with silicosis through the legal system, leading to manufacturers marketing “low silica” quartz at a cost premium. This premium is closing the cost gap with porcelain. This is the main economic and legal reason as jurisdictions- Australia and maybe soon California look to ban these products forcing the market towards natural stones.

If you’re then selecting from natural stones, porcelain is essentially used as printer paper for whatever stone pattern is desired, and given that people tend to want things that look like marble, this “ink” is essentially free for the manufacturing process, making the porcelain look like marble more than quartz or granite.

Engineered quartz is also not a great exterior material, again yielding to porcelain.