The only thing this thread proves is that people don't understand how bike steering works and what makes it stable. Has nothing to do with stem length. Zero length stems are a current fad in mountain biking, and I'm pretty sure mountain bikers need to be able to steer their bike. Someone mentioned the Pacenti P-dent stem above. Old news by now, but they were one of the first to offer really short stems. Only problem is you have to use their handlebars, so I imagine it will be short-lived. https://bikerumor.com/pacenti-p-dent...new-20mm-stem/

I had a related exchange on another thread where I offered to exchange free body diagrams (mechanical engineers should be able to draw an fbd) with anyone who thinks that stem length is an important element of bicycle steering. For some reason, nobody took me up on that. But one person suggested that the stem was required for the tiller effect. The the tiller on a boat has to be a certain length so the steering forces from the rudder can be counteracted by a person. For a bicycle, the tiller is the handlebar, not the stem