On my 372 build this is also true.
The reason on the 372 copycat is the upper AV buffer spring (right side between the cylinder and front handle), this is what determines the angle on the engine versus the rear handle on the 372 at least.
But; the angles you show on your picture might not be entirely correct at the parts either, so what you need to do if you want this to be as true as possible is placing your sweet baby on flat and level work table first and ensuring it sits perfectly level on the table, perhaps use some shims under the bottom part of the front aluminum handle to get it perfectly level to the table.
Then you measure the guide bar seat/mount surface with an 90* angle guide between the table and the bar seat, it should be 90*. If not, you can adjust the length of the upper AV buffer spring by using an angle grinder if it's too long or shim it with washers if its too short. Looks to me it's too long.