Comment by w10-1

OpenDoc was mostly given to Taligent (the Apple and IBM joint venture) to develop. It was full-on OO: about 35 files for a minimal application, which meant that Erich Gamma had to build a whole new type of IDE which was unusable. He likely learned his lesson: it's pretty hard to define interfaces between unknown components without forcing each one to know about all the others.

MIME types for mail addressed much of the demand for pluggable data types.