I'm making a general statement, not specific to UC Berkeley. Even if you don't consider UCB a business, most of its income does not actually come from taxes and its spending isn't going to be all that different from a private university. Clearly, their decision here was not to spend, but to delete instead. That was the economical thing to do.

You're also missing the point completely. Whether a business wants to do something depends on whether it is expected to be profitable. If the laws make it unprofitable, then it doesn't want to do it.

You're posing a false dilemma with "it's more important that those persons be allowed to participate in society than it is for a business to make money". If society wants participation, society should pay for it, not just business. It's just really easy for the government to use people with disabilities, because opposing such legislation is unpopular.

Who decides what's reasonable, anyway? If you're a small business, building some ramp can easily break your budget. If you're McDonalds, it make no difference. Are you going to treat both companies equally? If so, you're sponsoring big corporate.