The phrase "to destroy the competition" means to be so successful and better than others that they are unable to compete or succeed against you. Full definition
This device isn't meant to destroy the competition with specifications, it seems, but branding. (slashgear.com)
They put together a list of the top five speeds that players reached during the campaign, with a surprising star absolutely destroying the competition. (caughtoffside.com)
You want him on your team, he utterly destroys his competition. (nystateofpolitics.com)