No, Trump hasn’t "essentially repealed Obamacare"

The fear is that eliminating the mandate could produce a “death spiral” for the exchanges, where higher premiums scare away healthier customers, leading to even higher premiums and even sicker customers—until eventually,the insurers decide to bail. It could also encourage insurers to try to lure healthier customers with cheaper but skimpier plans that don’t provide protections for pre-existing conditions, since those customers would no longer have to pay a tax penalty.

But it is also possible that younger and healthier customers who initially bought insurance because they were required to do so will now buy insurance because they want to; surveys show that more than 75 five percent of Americans covered on the exchanges are happy with their coverage. And as a political matter, repealing the unpopular mandate could make it even harder for Republicans to pass legislation repealing insurance protections, Medicaid expansions and the rest of Obamacare, because the rest of Obamacare is popular. It’s not surprising that Republicans managed to kill the law’s vegetables, but it won’t be as easy to kill dessert.