[qiqing]

Excerpt from the article:

Jobs in health care, recreation and hospitality report the highest level of job openings, relative to employment. Many of these involve plenty of person-to-person contact, making their workers especially vulnerable to infection (a study from California earlier this year found that cooks were most at risk from dying of covid-19). By contrast, in industries where maintaining social distancing or being outside is often easier, labour shortages are less of an issue. The number of job openings per employee in the construction industry is lower today than it was before the pandemic.

[TheCoelacanth]

Those are also the industries that unceremoniously dumped a large portion of their workers a year ago. Many of those workers undoubtedly moved to other industries and now that they have gone to the trouble of switching, they aren't going to switch back without getting a much sweeter deal.