I haven't seen all of the evidence, only what has been posted on the news sites, but although I can see both sides I think I am on the side of agreeing that the sentence is fair.
From the facts I can gather: on the one hand, there's the argument that a cyclist should be on the road rather than the pavement (which is subject to it's own fine) and the partially sighted lady was startled by the oncoming cyclist. The lady did not physically push the cyclist into the road, nor did she cause the cyclist to fall off or lose control of her bicycle, which was what led to the cyclist being hit by a car.
On the other hand, the pavement has not been confirmed as a "pavement" and it's contentious as to whether bicycles are allowed there or nor. The pavement was 8ft wide, wide enough for both users to allow each other to pass. The lady did not say "please may you cycle on the road rather than the pavement? The pavement is only for pedestrians, not cyclists", she waved her arms and swore which could have frightened the cyclist into feeling an imminent assault was oncoming. This may have meant the cyclist felt pressured and panicked into rejoining the road when it was unsafe for her to do so, leading to her falling off the bike. After the cyclist is hit by the car, the lady does not stop to enquire about her wellbeing, nor did she show any remorse until the day of the trial, she went on her way and bought some shopping.
Whether the cyclist should have been on the pavement or not, she shouldn't have died that day. Although she was responsible for her own re-entry to the road and was responsible for keeping control of her own bicycle, it's likely she would not have felt the need to rejoin the road at that moment and in that manner if she had not been sworn and gestured at by the lady. The lady's actions caused the cyclist to take measures which led to her death, which wouldn't have happened if the lady did not take those actions.