Long-time Google ex-talent are calling the tech giant "unrecognizable"

It was clearly the closing of an era when co-founders of Google, Larry Page and Sergey Brin, officially left their positions as CEO and President of Google's holding company Alphabet.

While it's unclear what prompted the two to leave their formal management positions, longtime employees, many of whom also left the company this year, described to CNBC a massive cultural shift that percolated throughout 2019.

They cited changes to Google's all-hands meetings, human resources processes and transparency from management.

Alphabet CEO Sundar Pichai admitted the company's challenge in scaling the trust of its own workforce which numbers more than 100,000 people. More recently, Lazlo Bock, former Director of Human Resources for Google, told Bloomberg that he thinks Alphabet is "a different company than it used to be" but that "not everyone's gotten the memo."

The change has been noticed by some on the outside, too.

"What the hell is going on over there?" tweeted Andreessen Horowitz partner Martin Casado over the summer. "The brain drain at Google right now is astonishing."

Google declined to comment.

Read more here.