The only playoff teams we played at full strength with Mitchell, Allen, and those other guys were the Bucks (we were 1-1, and no the game we played them without Giannis doesn't count), the Kings, and the Clippers. We've beaten and lost to the Magic when were at full strength and we've beaten and lost to them when we were not). I'm quite certain the numbers would look a lot different as our margin of victory, when we won, was a lot smaller. But I'm not your research assistant, so you can look that up yourself.
There's a rather large postseason sample size of what Mitchell, Gobert, and a bunch of guys who like to move the ball looks like in the playoffs from his time with the Jazz. The reality is that model isn't that hard for good teams to beat.