The BigTech firms have been doing this intentionally for a very long time. I started hearing about Microsoft doing the security-escorts-you-straight-out-the-door all the way back in 2012.

It's not that they are bad at this, it's that they think the trade-off works out in their favour. And it probably does - what's a few but-hurt former employees, versus one disgruntled former employee who had enough warning to snag critical data on their way out the door?

Though it's probably our fault, since we're all so trusting of our mega corp employers, and/or so optimistic about our chances of surviving layoffs, that no one is stashing the incriminating data ahead of time.