Excel was completed at least a decade ago (probably two).
This is obviously 99% marketing. Microsoft/Waggener Edstrom tend to be really good at getting mainstream media to report on the marketing activities.
Example: For many Windows launches since Windows 3/95, there's been this media splash where Microsoft spends x million dollars on marketing and mainstream media then reports this, thereby getting (like) 100x millions worth of exposure.
Excel is not "complete" until they stop forcibly converting long strings of numbers into scientific notation - or at least give me a sheet-specific way to turn it off. I know how to stop it on my machine, but I have shared documents where if any one of the 16+ other users forgets, then it's messed up for everyone.
Let alone the date issues.
At one point I did a deep dive on one or the other of these "quirks", and the earliest request for exactly the fix I want is from nineteen-eighty-fricking-five. Unbelievable.
Yes, there will be edge cases. They need to balance historic compat vs one more fricking setting checkbox. I am thinking that you will never see this solved.
They've now made a change in that at least when you open a csv it now asks you beforehand if you want your data transformed, eg converting strings to numbers where that loses leading zeros.
def 2 decades - 2023 was the best version and it has been downhill ever since
I'll admit, on occasion having more than 65k rows is helpful but generally that's the domain of a database, not excel and it wasn't a good tradeoff IMO