Taiwo has a massively superior scoring record in a significantly worse team. In fact, if you look at both players' overall Premier League records he's a better producer of goals:
Delap: 13 goals in 3700 minutes
Awoniyi: 21 goals in 3350 minutes
I am supportive of replacing Taiwo, because I agree with your assessment of his skills, and his durability is not good. But Delap does not look like an upgrade in anyway except his fitness. You can tell me about the eye test if you like but strikers are paid to score goals, you don't pay £45M for a guy who creates space.