There is a difference between being in business and thriving.
I've been in a few companies that managed to eke out a living by maintaining a piece of software no one in their sane mind would still maintain. Sometimes a government gig, sometimes the private sector.
Shoutout to my boys that in 2018 maintained a Java 1.3 app. Still going strong to this day (it was migrated to Java 8 last time I checked).
EDIT: ~21 Delphi apps in world! Woohoo! Delphi number #525
Sure, either of them qualifies. I was just pointing out that Delphi (and C, and VB) aren't really widely used in GUI toolkits anymore.
It's not just the difficulty. It's the lack of learning materials, widgets, examples, and whatnot. Debuggers also suck, at least they did when I used Delphi.
What also helps is having a huge behemoth of a corporation improving your GUI toolkit for free (Chromium, although you pay in ad exposure).
https://www.embarcadero.com/products/delphi
One of the related conferences just took place last October,
https://entwickler-konferenz.de/en/