The 3pm Saturday tradition is attributable to 3 things that applied in the early years of professional football but no longer apply. That most people worked a half shift on Saturday mornings, that it was illegal to charge admission to a sporting event on a Sunday and that nobody had floodlights.
It’s curious how we are to it as a traditional time when none of these still apply. Is it really because, coincidentally, it’s still works for the way we now watch football, or is it just because we don’t like change? I like 3pm for an away day where you are writing the whole day off anyway, but for a home game, it can be quite intrusive.