The major sports leagues definitely favor high-flying offensive attacks. They believe that is what attracts eyeballs. It's also better for our soundbite-based low attention span society of fantasy football and NFL RedZone. There is an entire class of NFL fan now that doesn't even watch the games but instead just tracks streams of scoring plays for their fantasy teams on their phone with the TV on in the background.
Defensive battles that result in a score of 9-3 do not excite and create a Sunday afternoon nap on the couch situation mostly.
I don't think it's a good thing, but I see why they do it.
Personally, I wish we could just skip this intermediate crap and go right to gladiator fights between death row inmates. Whoever wins gets their freedom or at least the sentence reduced. That is where this society is headed. Let's just get there and get on with the Roman Empire collapse already!