Thomas' 19:05 TOI/game would be 4th on the oilers and his 32 points in 36 games would be 3rd on the team behind McDavid and Draisaitl. Buchnevich would be 5th on the oilers in TOI/game and also 3rd in points with 36 points in 37 games. Either one would instantly be the oil's 3rd best forward behind McDavid and Draisaitl (or second best if they for some dumb reason decided to trade Draisaitl).
Both of them play big minutes on PP and PK, and they are both also on excellent contracts with years of team control. Thomas is only 22, signed for another 1.5 years at $2.8 mill, and will be a RFA when his current contract ends. Buchnevich is 26 and signed for 3.5 years at $5.8 mill.
Nothing wrong with not wanting to trade Draisaitl, personally I don't think the oil should. However, you are woefully out of touch with the value and on ice impact of the two Blues forwards in this deal.