We have heard it before: the biggest issue with the Marvel Cinematic Universe (MCU) is the treatment of its villains. Either they are too underdeveloped or killed too early. At some extent, that's very true and classic characters end up as no more than footnotes or plot points to keep the machine moving.
But I am not writing this piece to add to the complaints, in fact I have always said that if you don't have anything nice to say, don't say it. And if you are going to voice your opinion, then do so by adding something positive. A critique is not always a negative one.