I can see your point, John. If all the engines one saw were conserved relics, then that would be just as dull as all the engines being as though they had rolled out of the showroom door!
I'm convinced that there is room for all opinions, as I find museum attitudes as irksome in respect of conservative conservation as the metal detectorist polishing a 1,000 year old artefact. Like both left and right wing politics, either extreme is terrible and similar in social effect.
Regards,
Kim Siddorn