What's wrong with this photo

Who needs to grow up?
If you require sharp and well exposed photos you have to have some basic knowledge and have to do some work yourself. If you expect forum "wizards" to guide you from very bottom to very top of photography craft, you expect too much.

In photography ability to set right exposure and test target is like potty training in terms of human maturity. And it's not "art", it's literacy.

I sometimes think some posters are just making puzzles for forum members.
There are several things that make it difficult to assess the lens sharpness. Most of them, but not all are in OP:

• high curvature of the subject so there is no idea where the focus point was - check.
• low detail subject so it's hard to estimate sharpness - check.
• low shutter speed so it's not clear if it's a motion blur or not - check.

What's missing is high ISO and moving target. With those it would have been a perfect riddle to figure out what's wrong with the photo.

And why to present puzzles to public? Common sense says to eliminate potential issues one by one until you find the the cause. Looks like OP doesn't want to do this work and you support it.

It really takes no more than will and basic common sense to start self education. Just google "how to measure lens sharpness", this will be a good start, more efficient than showing clueless snapshot.