>users of spreadsheets are already thinking in terms of matrices of values
I am pretty sure most users of Excel are not thinking about matrices. They are thinking of rows and columns. Programmers and mathematicians might generalize this to matrices and values, but the users themselves are not thinking about it. This is akin to viewing Tinder as a "human interaction app" and lumping it in with Slack under that abstraction, and not realizing that those are two very different use cases and mindsets of the user.
> The spreadsheet paradigm hides what's important (the formulas) in favor of the superficial (the data)
To most users, the data is what is important in a spreadsheet and the formulas are implementation details.