I don't think the analogy is right. If in this cow business everyone instead of transacting in dollars and milk supply contracts start using a whole new language called "ether" then your accounting platforms/accountant/electronic receipts are not made for it.
Even mainstream accounting stuff is quite flexible in terms of how you define functional currency.
Its really not something where crypto somehow magically requires different accounting calculations.
>whole new language called "ether"
Quite. Existing accounting captures custom written contracts all the time though. Defi while revolutionary in many way doesn't really change the dynamics on this in a way that affects accounting.
If you're still unconvinced look at Coinbase IPO. Did they tell the exhange no we can't file the usually accounting info? Nope...they filed classic USD financials.