Heaven forfend!
This is entirely possible. And with similar rosters, NU went from 68th in offensive efficiency and 91st in defensive efficiency in 2016 to 122nd in offensive efficiency and 42nd in defensive efficiency in 2017. So there definitely seems to be a give and take going on. Furthermore, the various injuries and illnesses required McIntosh to shoulder even more of the offensive load than before, and his efficiency sagged as a result. When he's hitting shots, the offense looks much better, and this was by far his worst shooting year.
That said, the biggest offensive issue facing NU this year was simply that the team did not have many good shooters on the roster. The only player seeing regular time that hit over 40% of his threes was Taphorn. (Law was at 39.9%.) NU saw good production from its big men when they handled the ball, but Lindsey, McIntosh, and Law shot .424, .404, and .403 from the floor respectively, which isn't very good. The team as a whole ranked 208th in eFG%, which isn't good either.
In 2011, to take a random example, NU ranked 21st in eFG%. (49th in 2010, 18th in 2012, for others.) I think it's a stretch to attribute a gulf that wide to defensive intensity alone, though I certainly think it's a contributing factor.
The added depth and talent should make the team even harder to defend, which can only lead to better offensive production while simultaneously giving the front-line players a bit more rest. I'm also curious to see how Falzon contributes. He has the reputation of being a good shooter but he wasn't in his freshman season, so hopefully he'll take a step forward.