I have been on the lookout for unflavored gelatin for the past 3 - 4 months. Most of the local stores usually only carry Knox-brand, but I found some generic, store-brand gelatin about 4 months ago. I only bought a small package to try it out before committing to getting more. Now I wish I’d bought a larger supply because I haven’t been able to find any more since then. (Haven’t checked Whole Foods.) It seems to be out of stock on Amazon.com too. But all I’ve been able to find about a shortage from a quick web search is an article from India saying that they are experiencing a COVID-19-related gelatin shortage there. Nothing about gelatin here in the US.
Maybe this will be an excuse to experiment with agar as a replacement. I use the gelatin for desserts.