I checked the report, but it seems at no point it seems to clarify what they consider "bot traffic". Is it measured in api calls, page views, or bytes? Generally the term traffic is meant as raw data transported, but in that context those numbers make no sense.
For example, one of the biggest traffic consumers in the Internet is video streaming. There's no way in hell that half, or even a tenth, of that data is fake - it would simply cost too much to waste it on bots. Both for the bot owners as well as the streaming providers.
This level of vagueness and lack of transparency (what do the numbers mean, and where do they come from) does not fill me with confidence on this report.
Take it away, Betteridge.