Earlier quoted context omitted.
It's as old as time. Or at least as old as the first few times mass layoffs and networked employee devices co-existed. https://www.nytimes.com/2001/03/21/jobs/laid-off-and-locked-...
Some companies do it, sure, but I wouldn't call it normal or acceptable. In fact, it's kind sleezy.
Some companies even do it after an employee submits notice on their end (paying through the end of the term but disabling access earlier than expected, or even immediately), though this is far less common.