The Perl 6 design process began in the year 2000. Concurrency and parallelism (two separate issues) did not become all the rage until CPU's hit the performance wall and multicore became more popular, which was--I think--after 2005 or so.

What leads you to believe it's not a focus?

from what i read online, concurrency is still a draft, its not implemented and that the killer new feature is its grammar and regex