Not all jobs are equal, some jobs require focus and creativity where it makes for a more valuable employee.
I think the exception is a job that requires the workers to multitask where pot does not do well.
My job requires focus and precision, I consider it a tool of the trade.
Some of the inability of workers to focus on a task can be blamed on the false premise that multitasking enhances job performance. Trying to multitask actually lowers your IQ as the mind becomes too scattered to perform efficiently.