They didn't cancel it. The city did according to this report.
Their insurance won't cover them.
And I don't think you can blame SXSW for not having Pandemic or War etc etc insurance, that seems pretty normal.
"South by Southwest's cancellation this year will not be covered by insurance, founders Nick Barbaro and co-founder and managing director Roland Swenson confirmed to the Austin Chronicle Friday. (Barbaro is publisher the paper's publisher.)
On Friday, Austin Mayor Steve Adler announced the March 13-22 interactive, film and music festival that takes place throughout Austin was being canceled by city and county officials over concerns about the spread of the coronavirus. After the announcement, Barbaro told the paper that the SXSW organization does not have event cancellation insurance that covers disease outbreaks or city-wide emergency declarations."
https://www.billboard.com/articles/business/touring/9330212/...