No one thinks it will be easy, or even that the Jays have an overwhelming chance at victory. It's that the Blue Jays are the overall stronger team in this matchup in nearly every respect.
Think about how nervous you are about sending Price or Stroman against the Rangers. Now think how nervous you'd be sending anyone other than Hamels against the Blue Jays lineup.
Of all the pitching staffs out there, it's the Rangers' who are the likeliest to get smoked by Donaldson, Edwin, Jose, and friends.