Most of the established large tech companies do User experience research sessions while doing several iterations of mocks during the process. This is prior to AB testing. My current and last company both followed this practice.
I happen to know several instances of Google, Amazon, Facebook, and even Apple not doing this. But I guess "established large tech companies" is a big list and GAFA is only 4 companies. I realize that these instances are not 100% of all the work those companies do. Would be nice to read more articles from them on their failed tests and what led to their current designs.
