Because we can. Because a compiler is nothing more than a fancy text translator.

It's super important because those concepts get measured, and absorbed into existing languages (as best they can), but that wouldn't have happened without the new languages

New concepts like Rust's "ownership model", Smalltalk's "Object Orientation", Lisp's "Functional programming", Haskell's "Lazy evaluation", Java's "Green threads"

A lot of my early expertise in performance analysis was heavily informed by my SIGPLAN membership. Many of the improvements showing up in compilers and interpreters would show up in some form there, and of course those developers were either involved in the papers or had access to the same research. So when some new version came out with a big explanation of what it did, I already had a reasonably good notion of how it worked.

It was a dark day when they got rid of the paper proceedings.

> I encourage everyone to create the most absurd, implausible, and impractical languages. Chasing the measurable is often useful, expressing the expressible is insightful, but never forget the true goal of language design: to explore and create what isn’t.

Sorry, but this sounds more like an artsclass to me. Don't get me wrong, there was a point in time where exploration of the unknown was the only way to move forward. But these days we would need greater insights into higher-level language semantics and inherent tradeoffs to guide language-design and language evolution.

There is plenty to choose from and one can learn already so much just by reading up on the Java-EG mailing lists. Brian Goetz has a true academic mindset and I frequently feel inspired when I read his reasoning which is both highly structured and accessible.

Otherwise we would just be left with another compiler class. Compiler basics really aren't that difficult.

That just is not true at all. These are all legitimate engineering tradeoffs, which any serious project has to balance. Calling this "aesthetics" is completely dishonest. These aren't arbitrary categories, these are meaningful distinctions engineers use when evaluating tools to write software. I think the students better understand what programming languages are than the teacher.

If you accept that a programming language is a tool and not just an academic game of terms, then all these questions have clear answers.

This reminds me of recreational math & gamedev, you simply do whatever you feel is fun and design it exactly as you'd like it to be.

I think it is more interesting to see which languages are still used today and how popular these are. Because this is also tied to the human user/developer.

For instance, I used BASIC when I was young - not as a professional but as a hobbyist. I liked it too. I wouldn't use BASIC today because it would be entirely useless and inefficient.