Personally, I've never cared for the curated data sources or to format my notebooks using fancy 2D typesetting or using math characters in my expressions, so I don't miss those aspects of Mathematica. Most people won't need like 95% of the shiny features in Mathematica or can live without them.
Some more interesting thoughts here and I agree with the author that inconsistency between packages is the main drawback with python. However in practice, you get used to it (and you can find inconsistencies in Mathematica as well). https://www.johndcook.com/blog/2010/07/09/replacing-mathematica-wit…