If developers want to build ugly tower blocks, and people would actually buy those blocks, why stop them? Just because I bought my house ten years ago doesn't give me the right to stop someone from building something "ugly". At least, it shouldn't.
It's important to remember that just because the law says, "you can now build a thing", that doesn't mean the thing will get built. First, the current property owner has to sell, and sell at a price that it makes sense to build the ugly thing. Then a developer has to want to take the risk of building the thing.
It turns out, making it legal to build things doesn't really mean they spring up instantly. It's a slow process that takes decades to play out.
In the 70s, a section of San Francisco that was zone single family only was rezoned to dual/triple/quads-allowed. Since the 70s, only a few of the single family have been torn down and replaced with quads.
