One other large issue is that less popular languages (CL, Scheme, Smalltalk, etc) sometimes just don't have the library you need or the libraries are immature a

One other large issue is that less popular languages (CL, Scheme, Smalltalk, etc) sometimes just don't have the library you need or the libraries are immature and not fully developed. Database adapters for something like SQL Server is a great example. Most languages have a Postgres library, but sometimes the business requires a SQL Server connection...it's rarely been by choice that I've wanted to use it, but by necessity. Another is Salesforce...I don't know anyone who would voluntarily want to work with Salesforce, but more and more it's often a requirement to have a working soap library, Salesforce client, etc. Sure, you could write your own...but I can't think of something less interesting to do in development, when you could just switch languages and integrate directly without having to write a lot of glue code. I do feel like I get more done in Common Lisp when the language 100% hits my use case, but it seems invariable that my use case involves external services I didn't plan on that have to be re-implemented or a work around/microservice written for them in a different language.