I didn't say that Vegas did not have depth. I said that it was primarily one line that did the bulk of the damage especially vs the Oilers. The point was that their best players were the keys to them winning as is almost always the case. Depth can make a difference. But you are not winning because of your depth if your best players are not good enough. And though I did not say so above timely goaltending is also huge. Had Brossoit not been hurt the Oilers probably win that series.
And again, what I said was you win with your best players and the best depth you can afford chipping in. Vegas was fortunate that some of their most significant players were on really cheap deals. This was also the case with Colorado. The OP's post suggesting that the Oilers trade Draisaitl to improve their depth would have been akin to the Avs moving Rantanen when MacKinnon's new deal came up, to keep Kadri and add some minor piece or Vegas trading Eichel this off season to keep Smith and sign a $4.5M second line winger.
Overall we agree that moving out star players is the problem that this org has had that cannot continue if we hope to have any success at winning. So we agree on that front
In fairness to me your preamble in the post I quoted Was " You don't win with depth" Followed later by "it was a myth last year that Vegas depth won them the championship."
Those are your statements, verbatim, which I responded to. Your wording was confusing.
Even within that your premise is inaccurate. Players like Karlson, Smith etc produced and contributed inordinately to what they had done lately, or even in recent series. Reality is that Vegas had 7 forwards producing. That isn't one line getting it all done, unless maybe you're focusing on Oilers series specifically.
Additionally Vegas having depth in D and in goal were keys to their success. Depth at all positions matters. Invariably it does in the long slog of playoffs.