You have to look at the film holistically to understand.
To understand what? That the plot and character developments didn’t match percieved expectations? Just because it doesn’t, that doesn’t make it bad nor does it mean hardcore Star Wars fans were intentionally jerked around.
I think what people ought to do, if they don’t like the film but want to, is to drop their expectations and go back in with an open mind. It doesn’t have to match what we expected for it; but if you do try to match it with the rest of the series, it does actually fit—just not in the way you thought it would. It casts the rest of the series in a different light, yes, but it doesn’t abandon it or ruin it.
That is, if people want to like it, they can adjust themselves to like it and to fit it without it ruining the OT. If they don’t want to like it, which many people (not saying yourself, mind you) are happy to just hear themselves complain, then so be it.