Because binning is expensive and increases the cost of processing geometry. It works on Mobile GPUs because bandwidth to main memory is very power hungry so eating the cost of binning is worth it when your power envelope is 5W and you just can't provide enough bandwidth to do immediate mode rasterization.
Desktop GPU's power and memory bandwidth budgets utterly dwarf what the mobile GPU has so paying the compute cost of binning doesn't make much sense because they can just throw more memory bandwidth and larger caches at it. Geometry binning and the kind of tiling mobile GPUs use has a lot of performance cliffs so it's generally avoided when you can. The second you go off the happy path of a tiler the performance drops like a rock, like in the compute example in the linked article. Desktop class GPUs can get most of the benefits of tiling by just letting their cache hierarchy do the 'tiling' for them to avoid hits to main memory.
Some desktop cards do some tiling work, probably to improve cache utilization, but they don't suffer from the same performance cliffs that mobile GPUs do.
Desktop GPU's power and memory bandwidth budgets utterly dwarf what the mobile GPU has so paying the compute cost of binning doesn't make much sense because they can just throw more memory bandwidth and larger caches at it. Geometry binning and the kind of tiling mobile GPUs use has a lot of performance cliffs so it's generally avoided when you can. The second you go off the happy path of a tiler the performance drops like a rock, like in the compute example in the linked article. Desktop class GPUs can get most of the benefits of tiling by just letting their cache hierarchy do the 'tiling' for them to avoid hits to main memory.
Some desktop cards do some tiling work, probably to improve cache utilization, but they don't suffer from the same performance cliffs that mobile GPUs do.