While testing for flu in the global sample is indeed down 21% compared to last year, positive cases are (currently) down 97%.
From their fortnightly report of 28 October 2019:
"data to FluNet for the time period from 30 September 2019 to 13 October 2019. The WHO GISRS laboratories tested more than 102881 specimens during that time period. 5005 were positive for influenza viruses"
And of 26 October 2020:
"...from 28 September 2020 to 11 October 2020. The WHO GISRS laboratories tested more than 81257 specimens during that time period. A total of 172 specimens were positive for influenza viruses"
From their fortnightly report of 28 October 2019:
"data to FluNet for the time period from 30 September 2019 to 13 October 2019. The WHO GISRS laboratories tested more than 102881 specimens during that time period. 5005 were positive for influenza viruses"
And of 26 October 2020:
"...from 28 September 2020 to 11 October 2020. The WHO GISRS laboratories tested more than 81257 specimens during that time period. A total of 172 specimens were positive for influenza viruses"