If you enter you bike in a show or a concurs, then you are putting the bike to be judged against its peers. Usually on the grounds of originality, desirability, or accuracy in restoration. So it is inevitable that a bike will be dissected as to its faults and merits (notice I put faults first as that seems to be how judging works!) For some getting it 'just right' is the reward for a lot of time and effort spent. Other might see it as snobbery and silver collecting, with a lot of polishing.
But if you have a bike that you know is not original, whether because the right parts were not obtainable or changes have been made for ridability/durability, then you can hardly complain if you enter it into a show and someone nitpicks it. You are entering the family mutt in with the show dogs. Even if it looks like an Alsatian, there still is that tail from the neighbor's sneaky dog... It may be the nitpick-ing is well intentioned, the author showing off their knowledge (presumed or otherwise), or even sour-grapes. But when you place a bike on show you agree to the terms, and that usually includes authenticity.
So if your machine is not competitive under those rules or than is not your thing, then use the bike in events that it is suitable for or shows with rules more to your liking. That means rallys where the emphasis is on riding and kicking up a little road dust, or displays that do not have judging, or permit non-judged entries (display only.) If you want to get it 'just right' and go for the silver then you can spend the next twenty years hunting down the right carburettor and trying to get it to work, ignoring the fact if they were so wonderful they would still be fitting them to machines today.
Each group looks down their nose at the other; the riders verses the polishers. Both have the merits and detractions. Without the purists we would have no examples of what the bikes might have been originally (ignoring those restored over the top), all the machines would eventually modified and ridden into the ground. Without the riders we would forget that the original purpose of the machines was to be ridden on the road, albeit now primarily as a recreational pastime and not daily transport. If you belong to one group, you can hardly expect to hob-nob with the other and not catch some grief over it. Otherwise develop a thick skin and if the bloke next to you says the color is the wrong shade then take your drink to another table; or smack him in the gob!
Personally I try to get the details right to the best of my time and ability. But I full realize that when I spend a lot of time carving a bracket out of solid to replace and look like a casting that was broken or missing, it really is destroying the originality. Nor am I one for polishing. I prefer to do them up properly once only, then let then age naturally. Some call it developing a patina and others gentle neglect! But I do not enter my bikes in shows. Trophy collecting is not my idea of a fun day out, it ties me down at an event all day, and here in the USA judges (and spectators) know Indian and Harley-Davidson inside and out but very little about Douglases.
-Doug