It was a minor route that it appears very few people used. Even with perfect hindsight it isn't much missed.The route to High Wycombe should never have been closed in the first place.
Who would even remotely consider going from Reading, Maidenhead or Slough to High Wycombe by train via Oxford or Paddington? There are regular buses.For those of us (in the Maidenhead area) wanting to get to High Wycombe by train, involves a long winded (and more expensive) journeys via Oxford, or via Paddington and Marylebone.