The way dynamic code works (classloader, reflection), methods being virtual by default, interfaces, the JAR archives (think NeXT app bundles),... all that is Smalltalk/Objective-C influence.
> A second phase would almost certainly involve some programming in order to set up a real system at CERN on many machines. An important part of this, discussed below, is the integration of a hypertext system with existing data, so as to provide a universal system, and to achieve critical usefulness at an early stage.
> (... and yes, this would provide an excellent project with which to try our new object oriented programming techniques!) TBL March 1989, May 1990
Objective-C had a wonderfully pragmatic approach to OOP, though it remained tied to the systems it was on because of the standard object libraries that enabled it. NeXT promotional materials really liked to showcase its suitedness to rapid application development, whether Jobs himself doing so [1] or in a staged competition with Sun [2]
[0] https://www.w3.org/History/1989/proposal.html
Hypertext systems preceded it by decades.
Objective-C has great as it might have been, didn't brought much to the table to those used to the Windows or Mac IDEs for GUI development.
The Next vs Sun marketing video wouldn't have been the same when placed against HyperCard, Visual Basic, Delphi or C++ Builder.
NeXT was almost bankrupt when they were pivoting into OpenStep, and not only was Java born out of Objective-C influences at Sun during the OpenStep days, Java EE was born from the ashes of an Objective-C framework for distributed computing at Sun.
It also once seemed like "object-oriented" would be important. Now it is recognized as a niche technique.