While I agree that Luton Aiport Parkway to Hendon Central is via Kentish Town and Camden Town (or even St Pancras, ie Zone 1) is non-sensible, and that right minded people would change to a bus, I fear you woefully underestimate the extent to which people navigate by tube map (which is why it so cluttered).
Checking the overall figures of rail journeys made by Oyster in 2023 (revealed by FOI-0938-2425), 81 passengers travelled to Hendon Central from Luton Airport Parkway, along with 56 from Elstree, 22 from St Albans, 25 from Mill Hil Broadway, 103 from Mill Hill East, and 125 from St Pancras International (sic – how, I wonder?). While low, I don’t think I would put these in the ‘highly unlikely’ category – the stats include 739 stations (or gatelines), a quick bit of analysis says that’s 545 thousand possible journeys, of which 104 thousand wern’t made at all (there were just over 60 stations from which no one travelled to Hendon Central, while 672 destinations were reached from Reading). How do those figures compare to what’s in the fare database, I wonder?