Fair enough. It sounds excessive, and perhaps even regressive, but fair enough.
Still doesn't mean the funeral is about Bucky though. As Steve2020 said, they could have killed her off between movies and you'd still get Bucky as the last war buddy.
The death might be for Bucky, the funeral is anyone's guess, but probably Sharon.
Your earlier outburst was quite misplaced.
As I said, if you don't want to see a point, you will never see it. You will just blah-blah your way out of this. Apparently in this thread Sharon's fans want to see Peggy's death as just a plot device to get Steve with Sharon. So one last time.
Because the rule is "Show, don't tell". Because Peggy wasn't just some minor figure in Steve's life during many years and 4 films (and the last one, AoU, even showed that he still thinks about her). It's the last Cap's film, so her funeral will be a beautiful conclusion for all this. Audience will care about her death and its effect on Steve much more, than about some barely known girl, happened to be relative to her. You can't just say: "Oh, by the way, she's dead. Lets go on."
Audience needs to see Steve's emotions, his grief in order to feel the rising of stakes and his motivation. And what is the better place to emphasize it all, if not at her funeral? And yes, it's Cap's films, so it's always about Cap AND somebody, so I shortly said, that it's about Peggy and Bucky. As you said:
Kind of like Steve and Peggy in the bombed-out bar, where they talk about Bucky, but the scene is really about the two of them, particularly Steve, and is called back to when Steve makes his sacrifice at the end.
Yes, it's about Steve's grief, how much Bucky meant to him, his guilt and his motivation for going after Red Skull, although one would assume, he would go after RS anyway, but they still felt the need to show this scene. It's hardly all about Steve and Peggy.
And as for SC,it seems like she's not THAT big character in this film to make the entire funeral scene just for the sake of her. Either that, or Russos just really don't like her at all, and were forced by Marvel to make her important, because they don't want to talk about her. They already said multiple times, how important will be Tony, Bucky, Natasha, Sam, Vision, Spidey, Black Panter, even Wanda (considering leaked promo-arts and the last official art, one may suspect, that Wanda even took Sharon's place in the battle). It's not like they have unlimited time for million of important arcs. It's not like Sharon's relationship with Steve or name "Carter" are some sort of a secret, EVC already talked out loud about it. It's not like Steve in CW will have time to stop and ask himself: "I'm attracted to the Peggy's relative. Is it weird?"
If they could make Peggy's death happen off screen only for the sake of someone, it would be Sharon. They could just show that Steve is really interested in her, so made a flashback about Steve calling her after TWS and discovering about "Carter", because it's not that kind of revelation at all to require an entire funeral scene. It's no good to show the audience, that Steve get to know her only because of Peggy.