No.
In the distance past (PDF 1.1, Acrobat 2.x), LZW was the only
supported compression format. However, Flate (aka ZIP aka LZ77)
compression has been available since PDF 1.2 (Acrobat 3.0), and
is the only type of lossless compression (for text and small
images) supported by HTMLDOC.
HTMLDOC also uses JPEG compression when writing larger
images.
At no time does HTMLDOC try to compress data using the
(inferior) LZW algorithm.