The Medieval Period is definitely considered to be roughly 500-1500, I don’t know what the heck that guy is talking about.
500-1000 = Early Middle Ages
1000-1250 = High Middle Ages
1250-1500 = Late Middle Ages
That is the dominant school of thought regarding periodisation of the Middle Ages/Medieval Era. The period of Late Antiquity may bleed into the early medieval age (the “Dark Age”), that doesn’t mean that those years can’t be considered Medieval as well.
I think we should all just ignore this thread and get some peace. There’s no serious discussion to be found here.