Lye itself is pretty low-tech -- but being able to safely and repeatedly hydrate and dehydrate it while controlling the heat transfer, that itself may require some finesse.

That's perfect! You can also dip dough into the NaOH solution and get nice crispy pretzels.

High-tech, by definition, is tech which can make high profit, i.e. c1 sand into $500 processor. Sand is not low-tech or high-tech by itself.

PS.

Quote from Wikipedia for downvoters:

High tech is often viewed as high risk, but offering the opportunity for high profits.

https://en.wikipedia.org/wiki/High_tech

Definition: "Technology that is at the cutting edge".

Fact: Chemically produced lye dates back to at least 1791 with the Leblanc process: https://en.wikipedia.org/wiki/Leblanc_process

Fact: green energy/renewable energy/energy saving technologies are cutting edge now.

Fact: your processor is made from sand which was discovered by first human ever.

Yes, it's a little known fact that Babylonians were casting huge perfectly pure silicon crystals. They were also pioneers in x-ray lithography!

Processors are made from sand in the same way people are made from carbon. You're skipping a few important steps.

Skipped steps are called "high-tech".

Who says that high profit implies high tech? Your Wikipedia link only says high tech often offers the potential for high profit.

Is the Large Hadron Collider not high tech if it doesn't turn a profit?

Is potential profit for Science and whole our civilization low in case of Hadron Collider?