I searched Printables.com and could find nothing that was a free-standing, plastic drinking straw holder.  All of the others were designed for metal or glass straws.  I just wanted something to put my plastic straws in.  So I whipped one up in Autodesk Fusion 360, sliced in Prusaslicer and printed in just over 5 hours on my Prusa MK3s+, in PLA at 0.3mm layer height with a 0.4mm nozzle.  Infill is 20% gyroid.  No supports needed.  I had great bed adhesion due to the large, flat footprint on the bed.

Dimensions are 106mm L x 54mm W x 122mm H.