Which part of those two sentences is a lie?

"The refined scissor mechanism with 1 mm of travel delivers a responsive, comfortable, and quiet typing experience."

Is any of that false? How do we know?

"Half truths are lies". The pp is saying they're lying because they didn't admit fault. What's wrong with a company trying to sell a product by outright honestly saying "yeah, we tried to balance usability and thinness, and we went too far, we heard your complaints, and we've gone back and refined our old designs". I mean, they can tell the truth the whole truth and nothing but the truth in an even more markety way if direct honesty is too much.

This seems like nonsense. Must they admit fault in every communication for the next three years? Must they use specific words while admitting fault?

There's nothing wrong with a company saying "we screwed up." Which Apple has done already. There'a also nothing wrong with a company saying, "This keyboard is great," if it is in fact great.

>The pp is saying they're lying because they didn't admit fault.

They pretty clearly admitted fault when they offered free out of warranty repairs for keyboard issues.