Not everyone has the skills and experience to be in demand. A lot of people feel their current job is the only thing standing between them and the food stamp line. These people should not have to worry about getting sick and losing everything after losing their job.
They eventually decided to take the job, but having to even consider healthcare access in that calculus is ridiculous.
This is even more pronounced with lower-wage employees. I didn't switch jobs for years because of benefits: At best, I'd have to pay for COBRA for 60-90 days, which would basically take all of my money and then some. But mine was also fairly cheap and I had good coverage, something that similar jobs usually didn't match.
https://www.hhs.gov/healthcare/about-the-aca/pre-existing-co...
If you let coverage lapse, plans were allowed to impose a waiting period before coverage for the existing condition would start.
Since 2014, the “fix” is that now it’s just required to always have insurance, or else you pay a penalty.
Then for the last couple years the penalty was repealed but the coverage for pre-existing conditions is still guaranteed, which does open up a hazard that people will only buy insurance after they get sick... but really the risk of a sudden health issue is still high enough that most healthy people will still want coverage.