My deepest dive on a single tank was 57m, and I wouldn't recommend that or try to repeat it. Down currents can be terrifying.

You're right that 45m puts of out of range of most divers, but it is definitely still a doable dive with decent divers on twins and a deco stage.

The visibility in the photo looks decent for a silty bottom, I wonder what the current is like since it is in the Nile.

I am also curious about what caused it to become submerged in 45m of water 1500 years ago.