OK. While the fact that she didn't get a funeral scene is a legitimate complaint, although it's not one I agree with, the notion that her death was "barely acknowledged" or that there wasn't any "remembrance", or that it was done just to motivate the men, is utter nonsense.
Immediately after the fact, we have that scene set at the lake where the surviving OG are processing what happened. We see pretty much all of the six stages of grief expressed in that meeting. It would be nice if they had time to group hug and schedule appointments with their therapists, but the clock is ticking. The universe is at stake. If Natasha herself were there, I'm sure she would start off her reply to this scene with, "If you boys are done gazing into each other's eyes..."
Then there was the aforementioned scene between Clint and Wanda at the funeral, not only acknowledging Natasha's death again, but Vision's as well.
Then, yet again, when Banner admits that he tried to bring her back with his snap but failed.
And this thought that her death was done just to motivate the men or that she was simply "fridged" shows a complete lack of understanding of, and utterly belittles, Natasha's sacrifice, her heroism and her story arc as a whole. This is the woman who once believed that she had so much red in her ledger that she would never make up for it sacrificing herself to save not only her best friend, but no less than half of the bloody universe itself. "To motivate the men..." Yeesh.