Capitalism is fundamentally flawed.

"An economic system is a system of production, resource allocation, and distribution of goods and services in a society or a given geographic area" Without consumption of goods/services, there is NO economic system.

Fallacy Of False Cause

This states that consumption is a part of the definition of economic system, and even within the quote provided that is not the case.

Programming language popularity is a major factor in deciding whether or not to use it in a project.

It's not necessary should be the most popular. Popularity just should cross some threshold to signal that it works.

Irrelevant Conclusion

The premise seems to lead to a conclusion about how popular something needs to be to be viable not that popularity is good