How about Elixir and Erlang? They do pretty much exactly what Kay preaches.
Interestingly, the OO model that Wirth and Gutknecht implemented in the Oberon system corresponds better to Kay's message-based vision than Smalltalk-80. Wirth arrived here not by trying to emulate biology, but by trying to avoid the V-Table.
Java implemented the Simula 67 object model, confirmed e.g. by a 2017 Gosling lecture (as did early C++ and Smalltalk-80 to a significant degree).
Interestingly, the OO model that Wirth and Gutknecht implemented in the Oberon system corresponds better to Kay's message-based vision than Smalltalk-80. Wirth arrived here not by trying to emulate biology, but by trying to avoid the V-Table.
Java implemented the Simula 67 object model, confirmed e.g. by a 2017 Gosling lecture (as did early C++ and Smalltalk-80 to a significant degree).