So the question is limited to Middle Age England.
The various kingdoms in Anglo Saxon England were gradually united over several centuries, with the more or less official date of foundation of the Kingdom of England being 927. A few centuries earlier was the period of what is called the Heptarchy.
The name Heptarchy implies there ere seven Anglo-Saxon kingdoms in England, but actually there were about twelve Anglo-Saxon kingdoms in England around the year 600, although only about five of them were powerful. So that implies that a low ranking Anglo Saxon peasant would have had about twelve times as much of a chance to see his king riding by as an English peasant would have after England was united into only one kingdom.
Very little was written about the political history of Anglo-Saxon England before about 597 when St. Augustine arrived to begin converting the Anglo-Saxons to Christianity. And even less is believed by modern historians.
But it is quite possible that the 12 kingdoms existing about 597 had been formed by combining smaller kingdoms that existed earlier. I once read a claim that sometime during the 6th century (from 501 to 600) there were hundreds of tiny kingdoms in Anglo-Saxon England that were later united into the 12 kingdoms existing by about 597, which would mean that the average kingdom would contain only about a few thousand people. So if that claim was correct it should have been easy for the average Anglo-Saxon to speak to his king a few times during various public meetings.
So unless one's definition of middle ages England begins after the period when there might have been hundreds of kingdoms in England there may have been a few generations when most peasants might have had several chances to meet their kings.