@SteveR Definitely. Not being an expert here, I still hope that a print that works with PLA should also work with polycarbonate.
And yes, I would have loved to get an Otterbox for it, but obviously there is none available. 
Yet, the case by @muon seems to be the best option I saw so far - and yes, I did lower my expectations regarding performance…
The other option I thought of was what I once tried for my Pinephone: Taking an existing Otterbox for another device and modifying it, e.g. by inserting a spacer. One could also make some cutouts and/or keep the outer rubber part but design a new "inner"part and print this one. However, this would be a lot of work. One the things that prevented me from daily driving the L5 was in fact the missing case. But with the recent GTK 4.18 issue and other unresolved issues, it remains unclear how long I would profit from a better L5 case. Hence, I wanted just a case that somehow works, and I hope this will do it.