I cannot say for sure, but based on information in other threads here, the problematic iPads or iPhones are older models w/limited RAM (1GB).
Any specific reason you’ve settled on a 6th gen iPad? You could future proof yourself a bit w/one of the newer models. All of the other models (i.e., mini, Air, Pro) all have more RAM, more storage, and a cpu that is 2 generations newer. Granted, they all cost a bit more. Lastly, the rumour mill has the standard iPad and probably the iPad Pro getting refreshed before end of year 