However, it sounds like the Creative Commons licenses put a bit of emphasis on the artistic traits on the protected material ("musical work, performance, or sound recording", "moving image") and are explicitly not recommended for software.
The Creative Commons licenses were created as an alternative to the open-source software licenses for non-software works, because the software licenses don't really work well for more artistic works while their creators might still want to grant freedoms to the recipients of the works.
The main issue here is the notion of "source code" that is used in many open-source software licenses, but that doesn't really make sense for non-software works. This immediately also gives us one very important reason why the CC licenses are not recommended for software works: By removing the concept of source code from the license, people can subvert the intention of the license. For example, if I were to create an application under the CC BY-SA license (with the idea that it would work similar to the GPL license), someone can legally make changes to my source code and distribute just the changed executable without making the changed source code public. They have to give rights to make further changes to the executable, but due to the lack of the notion of source code, the license regards the executable and source code as equivalent alternatives of which you only need to distribute one.
Another reason why the Creative Commons licenses are not recommended for software works is license proliferation. In software, it is very common that two or more works get combined into a larger derived work (think of creating an application that uses multiple libraries), and the more licenses that are in common use, the harder it becomes to determine which combinations are allowed and which are not.
In this context, I am wondering whether these licenses are adapted to the distribution of an Excel spreadsheet that could also admittedly be considered as a software.
The CC licenses are not specifically adapted to be applied to a spreadsheet, but I don't think they need be. Spreadsheets are usually fairly self-contained, so the issue of license proliferation is less of an issue.
To my knowledge, the risk of distributing spreadsheets in a format that is different from the preferred format for making changes (aka source code) is also negligible. This risk would be largest if the underlying algorithms would be translated into a different programming language.
Based on these considerations, I don't see a problem with using a CC license for spreadsheets, but I would recommend allowing a license change to a (specified) software license if the work is modified to be used outside the context of a spreadsheet application. The CC BY-SA 4.0 license already contains this possibility to change the license to the GPL.
