I agree with this and it's definitely true for me. The downside is usually that once you have working code, it's just too tempting to launch it as-is. Why wouldn't you if it's working or even close to working and you can launch it and start making money off of it? The best part of a Figma prototype is that you can't launch it and nothing about it is permanent. Really you don't even need Figma, you could use MS Paint or Whimsical or Miro or whatever. The point is that it helps to remove the temptation and incentive to "validate" and ship asap.

A landing page != a prototype.

A landing page ~= a prototype.

Are you advocating for that alternative syntax for "not equals to", or did you have some other point?

That means almost/approximately equal to.

It also means “not equal to” in at least one common programming language: https://www.lua.org/pil/3.2.html

And usually, “approximately equal to” is expressed in this way: “n = ~3”.

Which is why I asked.

If that is what they meant, then I strongly disagree. A landing page is nowhere near a prototype. A landing page could be an advertisement for a prototype, but not a prototype.