Yes, it is possible to do better with Excel. But I would argue what I posted is fairly typical for a large fraction of the Excel spreadsheets I have seen. I admit that I have not been in a company with people with advanced Excel skills that spend all day in it, like you might have in some financial firms. But I have worked with plenty of scientists and engineers, and what I posted was fairly typical. Actually the worksheet named "Constants" might have been Sheet2 or the constants might have been shoved somewhere below the data. Excel just invites this kind of code by hiding away features like named ranges. Even a lazy scientist programming in MATLAB would at least have named the temperature t and the voltage v. I am not sure if I have ever seen someone else use the Excel comment feature except for collaboration.
I took a course which used Excel for some moderately complicated equations based on a dozen or so of input parameters. After looking at a student's Excel worksheet and seeing the results were all messed up, the instructor proclaimed that it is impossible to debug an Excel worksheet. I proceeded to find the bugs in their worksheet, but it was definitely much harder than debugging a MATLAB program that did the same.
If you have zero programming experience, then MATLAB/Octave/Scilab might be a fairly steep learning curve. But if you have any experience with procedural programming, you should be able to get started quickly. Learning how to (mostly) get around loops through clever programming or the intricacies of indexing takes a bit longer. Many solutions you find for MATLAB will be applicable to Octave or Scilab with some minor modifications.
For me Excel (or other spreadsheets) is fine for simple problems with at most a dozen columns, a few hundred rows and no complicated math. But as soon as it becomes more complicated, I move it to a proper programming language. What if you want to do the same analysis for a hundred CSV files (common case for me). Sure, you could write some VBA, but at that point you have pretty much lost all advantages Excel had about being less complicated.
Just to be clear, MATLAB/Octave/Scilab are not my favorite tools either. I think the language is pretty ugly. But I recognize them as professional tools and have written a fair amount of code for them (mostly MATLAB). Excel mostly strikes me as a toy, despite said toy being used by millions of professionals.