While the SWR math usually uses a 30 year interval for its calculations, higher allocations to bonds become very risky if you need your stash to last significantly more than 30 years, which is suspect is why you don't see a lot of super high bond allocations being discussed here on the forums.
With high stock allocations, you just have to survive the first decade or so without taking a major hit to your principle and the total size of your investments will likely have grown large enough to last indefinitely, regardless of what the market does.* With high bond allocations, spending down your principle over 30 years is pretty much the price of doing business.
*At least assuming the stock market behaves like it has over the past 150 years or so. If the a major war (foreign or civil) is fought on US soil your life will be disrupted in major ways regardless of whether you've FIREd or not. Similarly for revolutions, societal collapses, zombie apocalypses, etc.