I don’t understand why the US continues to keep land borders between US - Canada closed. “ Sept. 20, U.S. President Joe Biden announced that land borders will remain closed to non-essential visitors, until at least October 21.” [CBC News]

I don't understand why the US continues to keep land borders between US - Canada closed. " Sept. 20, U.S. President Joe Biden announced that land borders will remain closed to non-essential visitors, until at least October 21." https://www.cbc.ca/news/canada/british-columbia/b-c-snowbirds-frustrated-over-another-u-s-land-border-closure-extension-1.6187850