I wouldn't think so. I've found that I run differently on a treadmill than street. Differing wear patterns probably are a result of that. I don't think it's the drop causing it.

I generally have two different shoes for treadmill vs street as well. My street shoes have more cushion.

I would think that, if anything, the increased drop would move your striking point towards the heel.

In any case, where you strike is more correlated with running speed and stride length.  Faster speed or shorter stride move the strike towards midfoot/forefoot.  Try to sprint all out and land on your heel or walk and land on the balls of your feet.

Are you running faster on the treadmill than you were on the road or with shorter strides?

I wear different shoes for running on the treadmill and running outside.

Saucony Guide 10's for outside running that have a 8mm total drop.

Brooks Adrenalin GTS 18's for treadmill running that have a 10.2 mm total drop.

I put over 1240+ miles on a pair of GTS 18's that showed slight wear on the ball area.  It all depends on your gait and running form.

You can’t really determine anything based on sole wear.

If you run against traffic, your soles will have a specific wear pattern.  Run with traffic, different.  (City streets are highest in the middle) Sidewalk, different.  Even specific pace on the surface will change it.  

Look at more brands than ON.  I don’t know of a single person who got a pair of ON running shoes and kept running in them.  They always came back to Saucony, ASICS, Hoka, or Nike.  ON shoes look good, but they lack some function.  If you look at many of their new performance shoes, they’re ditching the clouds sole things too.  Perfect example is the Federer.

Nothing wrong with Mizuno.  They can be heavier, but the new foam looks really promising.  New Balance is another good one I forgot in my previous post.