It's user's faults for using it in ways that it was never designed for.
Excel has always been about sticking numbers in boxes and calculating with them.
If you want unmodified string input, input strings into a tool intended to handle them.
Project specifications can be hard. Using 1) .xls files after they were superseded, 2) ANY data transfer method without considering capacity or truncation issues, speaks of incompetence.
People just double click the CSV and complained that it didn't do it correctly. It is the same situation with scientific research data that researchers don't bother to use escape marker or blindly open the file without going through the proper import process. Then they blamed Excel for the that without understanding how Excel works.
Yes, Excel does have their quirks. But there are ways around those quirks, they have thousands of thousands guides out there about Excel. There is no excuses for people to complain about Excel didn't do the way that users want it to do without looking up for information.
Double clicking the CSV should open the data import dialog.
And that's what you have in Excel. What gets displayed is a separate issue.
And no, you don't want to see exactly what you typed in, not in the general case.
And no, I can't believe I am defending Excel!