There is not a single internet user who likes cookie banners. Many may not understand why exactly they're so widespread, but everyone definitely knows they are "mandatory" in some way, and everyone would be happier without them. Also all programmers, designers and product managers know they are awful.

Yet these big corporate websites keep trying to blatantly lie to their visitors saying stuff like "we value your privacy" in the cookie banners, perhaps because for some weird reason they think that that will "soften" the negative impact of the banners.

Why lie? Why not admit the thing is being forced upon them and just do the minimal they're required to?

This is just one example case among many in which well-meaning people lie for completely unjustifiable reasons.