python+pandas [1] is probably quite an easy choice for most common things people would use excel for. And being in the python ecosystem offers lots of libraries for statistics, machine learning, signal analysis, plotting etc.
People like real time feedback it's why word is more popular than tex, all these tech folks pushing code solutions to wysiwyg software issues are missing the point.
[1] https://pandas.pydata.org/docs/user_guide/10min.html