Insurance companies have to make money, but that's not that good of a deal, and the payout isn't that high ($73k annually) considering you won't be doing much else.
"Long-Term" is sort of a scare tactic that is used to get you imagining that you're going to be needing expensive skilled care for years. That can happen, but isn't normal.
https://www1.deltadentalins.com/content/dam/ddins/en/pdf/car...
If you get the PPO, you have an in-network annual benefit cap of $2,500. So you're paying your insurance company to pay your dentist for you? And as soon as the bill gets large enough that you'd actually need insurance, they tap out?