This is more of a lore question, but I can't find any information on it in the 5e Monster Manual. Hopefully there is a lore wizard out there who knows something about this.
I recently bought some of the adult dragon miniatures released by Wizkids, and noticed the Adult Blue Dragon has considerably smaller wings than the rest. You can verify this by looking at the video comparison of all adult dragon miniatures made so far from The Gallant Goblin at the 2:25 mark. Do note that some of the other dragons are posed to be flying or stretching their wings, but still, the Blue Dragon's wings are considerably smaller.
This struck me as odd, specially since the only mention of size in the Monster Manual is that:
"[The Red Dragon's] wings are the longest of any chromatic dragon" (MM, page 99)
"[The White Dragon is] the smallest, least intelligent, and most animalistic of the chromatic dragons" (MM, page 102).
The Red Dragon miniature seems to be consistent with this information, but it is odd that while the White Dragon miniature should be the smallest according to the lore, the Blue Dragon is smaller, or at least their wings are.
I was going to chalk it up to some Wizkids inaccuracies in the production of the Adult Dragon miniatures line, specially since there was no indication that these were dragons at the exact same age, but then I noticed that the same small Blue Dragon phenomenon presented itself in the Tyranny of Dragons miniature line that had smaller scaled adult dragons from 2014. Here is a comparison photo from my minis. I do not have the Adult White dragon mini since that one was released in another set, but the Blue Dragon clearly has smaller wings that the others.
I also vaguely remember that the aim of this new line of Dragons was to standardize the size/wingspan of future Dragon miniatures, which leads me to believe that they had to double check this information before modeling the miniatures. It seems weird to me that in both lines the Red and Blue Dragon's wings are consistent, so I don't think it's an accident for the Blue Dragon's wings to be small.