This is why people need to learn math.
Let’s say that you’re getting by on around $25,000 per year now in salary or wages. That’s a gross of 25 k, out of which you pay FICA and Medicare (and which won’t be taxed after retirement), plus commuting costs (ditto), and other day-to-day work-related expenses. So the feeling is that you could survive on ~80% of your current salary, because you’ll still need to pay income tax on earnings that you receive from “traditional” IRAs. If you have a Roth IRA that has untaxed earnings, then presumably you could survive on even somewhat less. (But let’s not get crazy here.)
So let’s assume that in present-day dollars you really could survive on ~$20,000 per year (again, given the assumption of a present-day gross salary of around $25 k).
If you can earn roughly $12,000 from Social Security, that means that you need some source of capital to generate around $8,000 in earnings each year – in present-day dollars. Assuming a “good” rate of return of around 5% per year, that means that you need to have about 20 x $8,000 saved up somewhere, which really means that you need to have around $1.6 million in capital saved up and invested to make that return, year after year for the rest of your life. The reason you need to have the capital generate that income is that you’ll live, on average, at least 20 years after retirement.
What that means is that even “low” inflation is going to make that $8,000 worth less and less each year in relative terms to today’s valuation. If you start eating into the principal right away, then your money simply will not last your lifetime. (Even the current example assumes that you will eat into your capital, but the longer you can delay that, the longer it will last you.)
If you plan to retire on more than $20 k per year, then you need to adjust your savings amount accordingly. Not many people are doing that, apparently.
You can feel free to avoid reality if you want to, but you can’t avoid the consequences of avoiding reality.