When the legends, beliefs, and celebrations involving this creature call it a “dragon”….. it’s a freaking dragon.
This creature has two legs and four wings.
When the source material this creature is from decides that it is a “dragon”….. it’s a freaking dragon.
These creatures have four legs and two wings.
When the source materials they are from designate them as “dragons”…… they are freaking dragons.
These creatures have two wings and two legs.
When the creators and adaptors of these creatures designate them as “dragons”……
They are freaking dragons.
(that last one, Smaug, is also often referred to as a “drake” and a “wyrm” by the source material, as well! Though in the books he has four legs, not two! This was changed so he could he more expressive, using his wings as hands.)
The creators and adaptors of these source materials all had something we know as “creative freedom.” Sometimes, stifling peoples’ creative freedom can be annoying to them. Condescending to people with claims that all things must fit into a fictional set of labels of your choosing often has unfortunate results.
For instance, you can refer to that last set of creatures as “wyverns” all you want. Whether you see that category as a “type of” dragon, or a different creature altogether– that’s your choice. No one can stop you!
If I refer to one of them as a “dragon”, and you say, to my face:
“…..Actually, that’s not a dragon, it’s a wyvern”…
I will promptly shove you, and your entire family, into a locker.