That kind of makes sense because Jesus is a prominent figure in Western culture, while Mohammed isn't. So basically it's just westerners attacking their own because of relevance.
Attacking Mohammed wouldn't make much sense because most Americans wouldn't even know who the prophet Mohammed is. Instead they just say, "Muslims are terrorists that attack us because they hate American"
Think about it. For every TV show that portrays Jesus is a bad light, there's at least 10 TV shows that portray the "Muslims are terrorists" trope.
Marvel recently made the Ms Marvel TV series with a Pakistani Muslim lead and it confused the hell out of Americans because they couldn't see Muslims as people.