Unfortunately I am not familiar with wget for archival of a whole website, just
used it sporadically for single requests.

Comparison with Chrome is also a bit difficult, because Chrome saves one
webpage. But HTTrack has to inspect the downloaded artifact and need to apply
all these rules of following and not following etc. Something Chrome doesn't
do,
so less processing equals less time.

Are you still running HTTrack continuously?Guess, that's what I would just
do.

The forum post says:
"but the plug will be pulled sometime late this year or early next year."

So you may still ne lucky to crawl all.