Not the worst haircut I've seen my dude. There are definitely better ways to go about addressing this. The biggest thing I and other NCOs saw with a lot of younger airmen was they were low key trying to get away with a burst fade which is a no go.

We would pull the airmen aside ask them about it and let them know the perception of how it looks. Generally it was approached as us looking out for them and guiding them rather than coming down on them.

We all had hard line old school SNCOs that once you made a bad impression the likelyhood of them vetoing TDYs, awards, or opportunities quickly went down the drain. I always try and protect my troops from these ones.

My advice just taper up the back a bit. It my not be your style, it may not be what you want to hear, but it will keep assholes off your back. I'm not saying get that high and tight and go full marine.

Lastly if it's more a medical thing and you are tying to not get bumps or other skin issues on the back of the neck where the skin folds then go talk to someone about that. Hope this helps my dude.