Are they taking lost expected income as depreciation though?
No - depreciation is for capital assets. Think finite goods with a service lifetime. Most common to understand concepts would be like a car, a TV, a multi-media computing farm
But they can be intangible assets too, like Intellectual Property, trademarks, etc.
Depreciation is able get a tax deduction for the spending you put into that.. normally taken over an agreed upon length of time that matches the usual serviceable life of the asset. But in this case, Disney is taking an accelerated depreciation schedule because they want all the tax reducing advantage NOW to help with FY2023 woes.
Additionally you have write downs or full write-offs... which is when you change what was the expected value of an asset was. You basically are devaluing something to reduce your taxable assets. An extreme, but over simplified example would be you spent $100 million to build an awesome TV Antenna facility. Then, TVs became antiquated and no one needs your awesome facility anymore, and you don't expect it to generate any revenue. So as the business sees this facility will never make them any future money, it's not really worth a $100million asset anymore, so they will look to write it down (reduce its value) or try to write it off (eliminate its value). In doing so they reduce their taxable assets.. and in turn their tax liability.
So in Disney's case... they can be taking advantage of lower tax liability RIGHT NOW with the advanced depreciation and lowering their taxable assets by writing down the value of the assets they have accumulated to support and operate this thing. That could be intellectual property, it could be investments in patents, technology, R&D, product, inventory, spares, the improved space, etc.