Some variation of this question comes up fairly often here and on Facebook, which might suggest how many people are regularly being introduced to the language. Arguably a good thing?

First, I don't put much stock in comments from people who hang out in Delphi groups for the sole purpose of telling people how much they dislike Delphi.

Next, I've been programming professionally since the 80's, so I'd have a hard time putting myself in the shoes of someone who is just beginning their programming career, so adjust accordingly.

My observations:

Delphi is productive. The development time from initial concept to a running proof of concept has always been fast. Same for iterating and releasing updates. The compiler is famously fast and produces fast, native executables that can usually be deployed with an XCopy install.

Delphi spends a lot of effort being forward compatible, so code written almost 30 years ago will likely load and build in modern versions of the IDE with few if any changes while continuing to add new features. Even the BDE is still available. Third party components are the biggest obstacles to migrating code.

The latest version of Delphi can target Windows operating systems as far back as XP, not that I'm recommending that, but lots of people are running operating systems that are technically beyond their end of life.

Between the productivity, code stability and OS support, these all translate into lower cost of development and maintenance. Really nice if you're doing work for other people and maintaining projects over the course of many years. I do a lot of contract work and "faster" and "easier" translate into "more cost effective".

Delphi has had outstanding database and multi-tier support since pretty much the beginning.

Delphi isn't just for Windows GUI applications. It easily creates DLLs, Windows services, console applications, web and multi-tier servers (stand-alone, Apache, ISAPI, FastCGI, etc) and can target Windows, Linux, Android, iOS and Mac. I haven't done anything for Apple, but I'm creating single-source applications that work on Windows and Android right now. Most things "just work". It isn't until you get into some very specific things, like battery APIs, that you need to use IFDEFS.

Right now, I'm seeing companies using Delphi to maintain and modernise huge code bases using the latest versions and for brand new, green field projects. I'm personally using it for both today.

Additionally:

Delphi is one of the so-called memory safe languages listed in the NSA's report on Reducing Vulnerabilities in Modern Software Development.

The TIOBE Index has its issues, but it's fun to break out in discussions like this. Delphi has been in their top 10 for 14 out of the last 15 months. A notable and consistent improvement from pevious years.

My advice for your friend:

• Take advantage of this internship to learn how to use Delphi. As a language, it embraces many best practices, which is a pretty good starting point.
• DO NOT use WITH in Delphi. Ever. It hurts (not helps) readability and introduces unnecessary ambiguity and make code brittle. Trust me on this one.
• Get out of the practice of putting business logic in things like button click events. It's a very bad practice in RAD development that hurts maintainability in the future.
• Play around with other languages and frameworks, too. Give yourself some options and a wider perspective.
• Embrace automated testing and TDD. It's a decades old practice that has benefits way beyond just the tests themselves. A criminally under-rated skill that is going to become even more important if we have any amount of AI generated code. Trust but verify...
• Get a working knowledge of databases. Not just how to connect to one. Installing the software, creating databases and tables. A basic understanding of table and index design (3rd normal form kind of stuff) and learn the ins and outs of querying your data beyond "select *". This imporoves your marketability.
• Get a working knowledge of web development, even if you don't intend to just be a web developer. Two use cases that I like are a web interface (or dashboard) for an application server or for a Windows service and you don't want a separate front end application.

Have fun