It's more of a technical note, but probably the last really important change was the accrual basis, which, as far as I know, was popularized in the 20th century. This is the system of accounting where you record revenues and expenses when you become aware of them, rather than when you pay them, so many things end up being recorded as debts. Notably, this is the currently-accepted way of doing accounting.

    this is the currently-accepted way of doing accounting

Cash basis is also accepted, and generally used by very small businesses where accrual accounting is too complicated.

Cash basis is accepted for the purposes of taxes, but my understanding is that it's not acceptable for legally-mandated reporting. That is, cash basis is not among the generally accepted accounting principles.

Accounting practices, professionalism, standardization, etc have obviously evolved tremendously since then, the same way any technology does as adoption increases. Math wasn't fixed between the invention of numbers and the concept of zero, but it became far more powerful when you incorporated it.

Another way to think about it is with cars. Cars today bear no resemblance to what they looked like or were capable of when they were invented, but nothing around the core idea of putting an engine on wheels has changed. The airplane was different. (But so was the Segway)

As a CPA, double-entry accounting is sort of considered the founding of modern accounting. Everything else is a question of accurate recognition. Luca Pacioli was an Italian dude who was the first person to publish something widespread on double-entry accounting, although the same methods existed in other regions without any formal documentation.

https://en.wikipedia.org/wiki/Luca_Pacioli