The article doesn't equate "dumb" with "inexperienced". It equates dumb with "makes wrong and dangerous decisions". In this context, you probably do not want i

The article doesn't equate "dumb" with "inexperienced". It equates dumb with "makes wrong and dangerous decisions". In this context, you probably do not want industrious people who will consistently make mistakes and create more work and a mess for others to clean up. The dumb also do not learn from their mistakes -- they are not simply inexperienced.