How do you know how old it is? And would it be in the same condition encased in amber as encased in bone?
"How do you know? Where you there?"
The image is an insect fossil dated to the Devonian. That's something like 350-400 million years old. Though it has been totally fossilized, its physical shape is in excellent condition. Of course, it woudn't be in the same condition. Bone fossils in earth calcify, while insect fossils are permiated by the sap.
In this article, they took mineralized tissues and soaked them in a mild acid bath that would eat away calcium. What was left were some tissues that had not *completely* fossilized.
If the physical structure of a 300 million year old fossil may remain largely in tact, why should it be impossible that some tough connective tissue not completely fossilize when surrounded and permiated by minerals?
Science has always described fossilization as a gradual process. That we should find partially fossilized tissue, as exciting of a discovery as it is, should not be construed as the downfall of science.