Currently if you sort by last watched date descending to see your most recently watched items, items with unknown watch date are at the top of the list. I think it would make more sense to treat unknown watch dates as an old watch date rather than a new one. My reasoning is that if you don’t remember when you watched it, it probably wasn’t recent - so better to treat it as an old entry rather than a new one. So the sequential order would be unknown watch date (perhaps sub-sorted by release date) < oldest watch date < newest watch date.
