@DGedye Promotional pictures show all antennas in perfect 90° because it's more pleasant to look at, more streamlined and easier to understand proportions. Also, they make the most of the image space because it forms a square rather than a rectangle, so there's less wasted empty space and typical square miniatures look so much better.

@Kevin_Z 

Thank you for reassuring me that I don't need a bracket to wall mount it . Perhaps the setup guide or manual could also mention which kind of screw fits the hole because I have tried quite a selection without sucess.

Speaking of setup guides I have now checked the Archer C7(EU)_V5_Datasheet, Archer C7(EU)_V5_User Guide, and Archer C7(EU)_V5_Quick Installation Guide and they all have drawings showing the antennas straight up. There is nothing in any of the guides or manuals to suggest the outer ones should be at an angle. Perhaps that should be corrected because I set it up initally according to the included guide.