It may be true that you have spent efforts, but I think there is a discrepancy between how the public and you perceive the value of the results.
I believe the public mainly values the ability to provide new aesthetic experience. So when you exposed your drawing without context, the viewer consider that all your skills and effort contributed to this new experience and are thankful (see fig. below).
But when the reference appears without context, it radically reframe the perception of the efforts. Your hours of drawings only contributed to deliver an inferior version of the reference.
Actually, emphasizing how much efforts you spent to butcher a reference worsens the reception (see fig. below).
I believe the reaction would have been positive from the start if you framed your effort to show how far you can go from scratch to reproduce an ideal, because it implicitly convey your hope to deliver new aesthetic experiences of better quality in the future (which is what the public value).
In response, the viewers would be much more understanding about the lackings of the drawing. They would have given you few words of praises and pat to the back to manipulate you into continuing your effort to give them something nice to look at.
Edit: The reaction discrepancy is just a play on the expectations of the viewers.
For instance, a musician is expected to
interpret a composer's music rather than composing his own piece and playing it. When someone plays a piece, people will automatically consider the efforts taken to learn and personalize it (which is neither superior or inferior to composing itself) and exclude the musician's contribution on the composition itself. The listeners might go 'WOW' when they reevaluate the fact that the musician is the composer too.
In graphical arts, artists are expected to do the entire process ex nihilo unless stated. But it doesn't remove the value of your efforts itself to make this drawing just like how a musician is working a damn lot. It is only reevaluated in a different way that could be disappointing compared to the first evaluation of the art in the usual context.
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That's how I imagine the public's mind work. I don't speak for everyone, instead I can only attempt to watch things unfold and explain them afterwards. I don't bargain with the public either, I just shit my art out and whether they like it or not is their problem.