Added clearance for washers to screw holes. Added small arm coupler. This is for lighter weight items. This is for the small arms. Use tree support when printing (see pic) 30% infill and 0.3mm layer height. Picture does not show but I added back in the 75mm holes. Tweaked in TinkerCad: https://www.tinkercad.com/things/bb4dIp8uAWt-vesa-plate-75-or-100-extend-arm-small-published/edit (Note: Depending on how your tree supports came out you might need to grab a small file and do some post processing work.)
The author remixed this model.
Added clearance for washers to screw holes. Added small arm coupler already built in.