Nah, just pushing back against Hfboard's tendency to blame support coaches for things.
"Craig Simpson is ruining the Oiler's special teams!"(Mact revealed a year later that he always ran the special teams)
"Chabot is ruining the Oiler's goaltending!" (terrible rosters and Dallas Eakins are what did that, and Chabot went on to work just fine with Dubnyk/Talbot in Minny)
"Woodcroft should be fired for reasons!"(Now people want him to be the next coach due to his work in the minors)
People like to have a scapegoat, and what's easier than a guy behind the scenes?
At this point, both Smith and Koskinen have had good and bad years under Schwartz, and Smith was perfectly fine working with Schwartz most of the year even accounting for the offseason consultant. It's more than likely Koskinen had issues behind the scenes(fitness or something due to covid is highly likely), and/or the rough start destroyed his confidence and it all snowballed from there. No conspiracy theories about the goaltending coach ruining everyone required.