According to the ARRL Letter, the growth has come at the expense of contacts made using traditional modes. The report draws on data from more than 84,000 logs uploaded to Club Log, representing some 730 million contacts. Looking back to 2015, Club Log reports that the "typical call sign" at that time made 620 CW contacts, 558 SSB QSOs and 372 digital Qs. In 2020, those numbers were 500 CW, 300 SSB and 1700 digital.
FT8 was introduced in 2017 and permits contacts to be made even when signals audibly are below the noise level. (It will be interesting to see if the trend continues as solar cycle 25 rises, with more band openings that make SSB and CW QSOs easier to complete. – ed.)