Ignoring all of the politics of "Free Software" and/or "Open Source Software", as a practical matter languages that are not available in no-cost implementations

Ignoring all of the politics of "Free Software" and/or "Open Source Software", as a practical matter languages that are not available in no-cost implementations are rarely successful outside of very niche markets. Though, arguably, the type of stuff Mathematica is used for is already sufficiently niche that this is less of a concern.