Pensions formed a compelling reason not to quit or get fired. Having to switch jobs came with substantial risk/drawbacks. That's not true today. Most people don't have any drawbacks to switching jobs other than the job itself. From a pure optimization perspective, quiet quitting offers workers a "reset period" where they can mentally reset before they quit/get fired and start a new job.
It's an extension of an environment that rewards switching jobs more than keeping jobs.
I think the proclivity towards trying to punish QQs rather than preventing people wanting to quit is only going to make it worse.