The list of used templates doesn't seem to get updated, as reported at https://www.mediawiki.org/wiki/Topic:U8ppxet08jlxb0r5
This feature seems to have existed since T154598: NWE should implement a replacement for "Templates used on this page" feature but doesn't seem to be working as expected.
Can't NWE extract this information from the DOM by looking at mw:Transclusion typeofs? I don't think Parsoid should generate more data / output for this use case since it seems easily derivable from the HTML.
I am going to remove the Parsoid tag from this. Please re-ad with additional clarification if Parsoid needs to do something special here.