What should I know about the delta variant?

Google South Korea Delta Plus Covid

That's not true

Yes it is, the article is talking specifically about the situation in the US, where most of the hospitalizations and deaths are from unvaccinated people.

Eventually enough people will be vaccinated so the numbers will obviously include more and more of the vaccinated population (while the rates will likely keep being higher in unvaccinated people) but at this point the US is still seeing a much bigger problem in unvaccinated people, that fortunately is not observed in other countries where rational considerations are still more important than perceived political meanings in being vaccinated.

Probably the number one fact to be known is that the vaccinated are the Trojan Horses of Delta and account for its highly accelerated transmission, Another little tweak of natural selection and it could be November of 2019 all over again and a scramble for a new vaccine and six feet apart and social distancing and masks upon masks and, from what we have seen of how little it takes to make masses of Humans who cannot go out and swill what is in effect an embalming fluid crazy, complete social breakdown...ah, Man the 'Wise', what has become of you? Or, are we just getting to know you better?

but COVID-19 vaccines still provide strong protection against it.

The ‘strong’ you just can omit. That’s only true for about 39% of the cases or so, considering the results of a study they made in Israel. Vaccination is very important and recommended, but it still remains a gamble afterwards, as you just aren’t completely safe against COVID-19.

The US should be looking ahead to Lambda, circulating in South American since summer last year. A recent study in Japan shows it may dodge the current inoculations. It is already showing up in South Texas hospitals.