They did, but that was not a Smalltalk heritage.

It surely was, here is some learning material.

> Strongtalk is a major re-thinking of the Smalltalk-80 programming language and system. While retaining the basic Smalltalk syntax and semantics, it contains a number of significant advances, including:

> The Strongtalk system was developed in secret in the mid-90's by a small startup company. Before the Strongtalk system could be released, the company was acquired by Sun Microsystems, Inc. to work on the Java® virtual machine.

http://strongtalk.org/

I'd disagree with that characterization. The earliest work in optimizing highly dynamic languages was done in Smalltalk[1] before continuing in Self. David Ungar was the through line and one of the original designers of Self.

[1] https://www2.eecs.berkeley.edu/Pubs/TechRpts/1986/5376.html

> The earliest work in optimizing highly dynamic languages was done in Smalltalk

Hard to believe, given that optimizing native code compilers for Lisp were already available.

I’ll accept “of the specific thread that led to HotSpot” as a qualification, sure.

Not true as the ParcPlace SmallTalk(s) were all JITed.