I mean put it into perspective. There's 300 million Americans who will live on average 15 years in retirement, currently at an average retirement income of $75k. So this group will be spending about $1 million in retirement per person, so for 300 million Americans you're talking about 300 trillion in spending during their retirement.

Now you take the most wealthy and successful corporation in the history of mankind, Apple, take its cash reserves (250 billion), subtract its debt (100 billion), and tax it (e.g. 10%) and you're left with 15 billion, which gives you the fraction 0.00005 of the 300 trillion you'll want to raise for US retirement of everyone alive in the US today. So in actuality you'd need to have another 20 thousand Apples, and you'd get to your number, just for the US population.

Ignore of course the rest of the 97% of the world population, despite Apple having earned its cash reserves from its global business, they'll need to find their own first-in-class corporate behemoth to tax for their retirement.

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I think more importantly, you have to acknowledge that money is just a tool for expressing value, but fundamentally has no value. What does have value is actual production. Everything that the people of the Earth can produce in a given year, and consume in a given year, constitutes their wealth. The more people work & produce, the richer we are, in total. Apple could have 1 quadrillion in cash, if nobody on the planet is working, Apple and everyone else is extremely poor. Retiring simply means: you do not produce, but you do consume what others produce. And that's fine if it's sufficiently balanced, where the working produce sufficiently for their and the non-working's consumption. And in France it was extremely clear from all studies that this condition wasn't going to be met the coming decades. Raising money through taxes doesn't change that fundamental truth, that this system is only sustainable if it is balanced, and it wasn't.

To simplify it, if every working person produces 2 loafs of bread, and every person eats 1 loaf of bread per day, in a population of 10 people you need 5 to be working, and 5 can retire. 10 loafs are produced, and 10 loafs are consumed.

If the retirement age is low enough that 3 people work and 7 retire, you'd produce 6 loafs, but the population still needs 10 loafs to consume.

Taxing companies in this population to finance this earlier retirement age, just puts money in the hands of the 7. It doesn't change the fundamental issue, which is that there's 6 loafs of production and 10 are necessary. So you'll see rapid inflation, bread becoming very expensive, some working and some retirees having no bread, in other words, poverty, versus the situation where the retirement age was a bit higher and all demand was being met by supply.

Of course actual economic models are way more complex, but this example illustrates: it's not money, or taxes, that constitutes or generates wealth, it's just a unit of account. What makes us wealthy is that which we produce. And human activity (= work) is the engine of that production. Reducing the retirement age = less human activity = less work = less production = less wealth. You can put taxes at any level, but that remains true. And France chose heed this rule, because all actuarial & demographic tables showed it can't sustain the wealth with the growing number of retirees, lower number of working age population, and growing life expectancy, at the old retirement age.