I'm pretty sure nobody on here hates SJ. This is just something his critics are sometimes accused of by those who do not accept that others may not think he is actually as good as they do.
I think that most will agree that he can, and has, made some quite superb last ditch reaction saves, often preventing a goal. Few of us have any complaints about this part of his game, and fully accept that he can be exceptional at times. Where the criticism stems from is a lot of errors early on in his time with us, when he was instrumental in us losing points. He has since reduced the number of such errors but still some of us cannot trust him. He has never been a goalkeeper with 'presence' in his area and unfortunately this has not improved greatly, nor has his reading of the trajectory of crosses and shots from distance improved at all. The may have also been concerns about how well SJ actually 'read the game' but I believe there has been some improvement in this over the years. These aspects must be something he has worked on with the specialised coaches, but it seems after so long, there is likely no improvement to be had, or at least none that I have seen.
I have never intentionally criticised SJ as a person, nor do I believe any other of his 'critics' would do so. I'm proud as an Albion supporter and pleased for him being chosen to represent his country.