I've looked at this article titled [Design Principles Behind Smalltalk](http://www.cs.virginia.edu/~evans/cs655/readings/smalltalk.html), and I can't see anything in Smalltalk that's not available in Java or Kotlin as well. I understand that Smalltalk is where the OOP ideas originated, but is it worth learning Smalltalk in 2019, even if just as a side project, for an amateur programmer reasonably familiar with OOP principles and techniques?
The idea that Smalltalk is a fully featured system which provides you with everything you might want to do with a computer reminds me of Emacs and Temple OS. Also, the blog I mentioned above seems to present Smalltalk as the perfect programming language.