I worked with Delphi in the beginning of my career, and the only thing I find myself really missing is the runtime type information! It worked really well and sometimes I find myself missing it in other compiled languages.
But I heavily disagree with the author's positivity about Delphi in general.
The UI builder excels on wiring up small utilities, but when you are looking to build applications with more complex UIs, with custom components and/or devices with different screens, the complexity increases exponentially and the UI preview becomes just a small suggestion, I think only in the last release (10.5) in 2022 they addressed this.
The component system is clunky, and very prone to breaking. In my entire time working with it I never once had a completely functional development environment, because components installation never had the same result. To work in some parts of the project i had to just ignore the IDE and edit the text files directly.
Also, Delphi updates required reinstalling everything, and solving the many problems that would arise, and then all dev environments would have to be reconfigured (and troubleshooted) manually.
Talking about editing, the IDE's performance is not very good, and the Intellisense is not asynchronous, the suggestions and error checking took their time to load, and the IDE becomes unresponsive while it processes, and sometimes windows would just kill the application because it was not responding. I had to turn it all off to be able to work. Oh.. And the bugs, the IDE had bugs just everywhere!
The above exposes a problem in the language itself, it did not have good asynchronous behavior, and I never understood it completely, the only way to make sure you would not block the main thread in some way was to spawn a new process to run background stuff.
The standard components are outdated, the WebView they used was Internet Explorer's one until the 10.4 release, in 2021, they just recently started to adopt WinUI, so you were stuck with 00's user experience, their JSON parser was not very standard (it didn't support the number type, for instance). And when I searched community components to implement things I usually found only something very outdated and unmaintained, or just didn't find anything.
I think essentially it had some quite good ideas in the beginning, but this is the important fact, it "had". Delphi stopped improving on itself, and is just trying to convince the same community of people who fell in love with it when it was still good and dedicated their entire careers to it that they are cool now, adding things that sound cool, while nothing important really improves.