Basic idea of double entry bookkeeping is that if you borrow money, it represents both an asset to you which you can spend, but also a liability (for the lender the reverse is true) because you have an obligation to repay it later, and that any accounting system should reflect all this lending that goes on. Knowing what they owe and are owed in future is as important to banks as knowing what payments they've just received and just made.

She's contrasting that with a "techie" view where all that matters is securely and immutably recording the fact that a borrower has received the "coin" (which represents mainstream blockchain implementations, though I'm sure blockchains could be designed to reflect debt relationships and even enforce debt repayment), and suggesting that what the distributed consensus actually records is only a subset of the relationships a centralised accounting/clearing system deals with.

She also pointed out that our financial system being built around debt relationships actually guarantees there will be some non-zero level of demand for dollars/Euros/Yen etc in future, whereas building the Bitcoin ecosystem around who holds the Bitcoin at a given point in time doesn't actually guarantee people will still want them tomorrow (especially if they owe repayments on dollar-denominated debt to buy BTC or mining equipment)

OK, that's essentially what I got, but that seems to refute the idea that blockchain should be used to replace all accounting(!), which is something that I never saw anyone advocate for. Bitcoin is just electronic cash, and that's how it was presented. And which can be, or not, tracked by accounting systems.

It just reads like a poorly structured argument against a huge strawman.

It's not particularly well structured and veers in the direction of straw man.

But most arguments in favour of blockchains as a superior way of doing things are centred around the idea that replicating cash is the most important thing about building a monetary system, when cash is actually the least important (and most likely to be deprecated!) part of the monetary system the world today is built on. If you still need a separate authority or method of reaching consensus to reconcile debts, then making the record of who controls the assets independent and immutable is a bug of the monetary system rather than a feature.