How often do we have an accurate reference on how it looked in theaters?

Also, is how something looked in theaters, say, 95% of the time the way it is supposed to look from an objective/absolute standpoint? Does such a standpoint exist without direct words from the director/production?

On top of that and on the other hand, how many times have we seen/heard directors/production say things that seemingly seem counter-intuitive or subjectively wrong in context to selling something that was "re"-done?

Also, is it reasonable or unreasonable to say that things like black-crush and white-blow-out, which seems like could be a result of simple brightness differences, could be vastly different from theater to theater, given the print, environment, health/eyesight/memory, and contemporary environment changes for re-screenings of vintage prints?

Again, if you've gotten this far, I'm think it would be good to provide much more context for preservation ideas and requests.