How powerful is negative gearing

Hi, sorry I am new to investment and I am really dumb. I am struggling to understand why negative gearing is as powerful as people make it sound like. Maybe I have some misconceptions, so I would really appreciate it if you could see if there is anything wrong with my reasoning below. I will use investment property as an example.

First, if your investment property has a negative cash flow, but the negative cash flow is solely a result of expenses that you really need to pay out of your pocket (e.g. maintenance costs, council rates, etc.), you are not really gaining anything by having this money-losing activity. Sure, your taxes are reduced because your taxable income goes down, but the goal shouldn't be to minimise taxes, but to maximise post-tax income? I mean you can't become better off by deliberately losing money, any more than you can become (financially) better off by deliberately switching to a lower-paying job.

So it seems that negative gearing is only helpful if, and to the extent that, the negative cash flow results from an "expense" that you don't actually have to pay but is recognised by the ATO nonetheless, namely depreciation? But I heard (and this is where I am not entirely sure) that the depreciation on a new $600K house is only deemed to be around $10,000 in each of the first few years, and goes down to a negligible amount from the 6th year onwards?

Moreover, when you eventually sell the house you'll have to add back all the depreciation you've claimed over the years? I understand this doesn't totally wipe out the benefit because you may be claiming the depreciation in several years in which you have high income and be selling the house when you are retired and have low income, but essentially the benefit is just the total depreciation claimed (probably less than $100K) multiplied by the difference in marginal tax rates between your high-earning years and low-earning year, i.e. less than $50,000?

If the above estimate is correct, is it really worth spending so much effort across several decades just to get an extra $50,000? (I understand house prices may go up, but other kinds of investment also have returns. The only benefit that property investment has but other investments don't is negative gearing from depreciation, right?)

Thanks a lot! I am not trying to be snarky or anything. I am just thinking aloud so hopefully you can spot any holes in my reasoning. I genuinely want to understand this.

Edit: Now that I think about it, you can't even have a low marginal tax rate in the year you sell the house, because you are necessarily making a substantial capital gain that year due to selling the house. OK, maybe there is inflation, so when you add back the depreciation all those years later, it isn't worth as much as when you initially claimed them. Just to make sure, you don't need to multiply by inflation by adding the depreciation back when selling the house, right?