Mexico's tourism has already been devastated.
Things have been extremely bad in the tourist sector before this announcement. Last year Cancun had less than 35% occupancy. Hundreds of businesses are "out of business". Tens of 1000's of people have no work. There are no covid checks, no unemployment checks, only hunger.
A couple of weeks ago when I was in Tulum, I took a former employee (friend) to Chedraui and bought her and her kids about 3000p in groceries. They have been surviving on eggs, beans and rice for months. Chicken and pork are a luxury they can not afford.
If you are afraid of getting sick than you should stay home and protect yourself. Don't go out. Luckily you can have all your needs delivered. That is the only way to be completely safe. You can not count on a government, your neighbors, and apparently a vaccine to keep you completely safe.
Don't stop others from living the life they chose, if your government allows you to still make personal choices.
Mexico has been very smart not to enforce the so-called closing of the border. It would harm more people than covid.