The reality is DTP outside of pro sectors (i.e. these days InDesign) was rendered worthless by how ubiquitous the tooling was.
In any sector where the barriers to entry are destroyed you either have to go really big or go home.
In any sector where the barriers to entry are destroyed you either have to go really big or go home.
1. Printers stopped catering to semi-pros and became more binary between "home" and "enterprise" solutions, with very little crossover and with "home" products trying to be as "good enough" dumb as possible (and also in many cases nearly as hostile to semi-pro usage as possible because so many "home" printers became loss leaders for ink cartridge subscriptions).
2. A lot of DTP moved to web publishing. Who needs printed invites when you have "evites"? Who needs printed greeting cards when you have "ecards" and now Facebook walls and group messaging stickers/gifs/memes? Etc.
I have fond memories of the home DTP creative scene in the 1990s. Partly because my mother was deep into it and very creative with it. It is interesting how much has changed between that era (when Publisher was one of several nearly ubiquitous home tools alongside Print Shop) to today (where Print Shop is a dead brand for many years and Publisher has been zombie-like or comatose in the same span, and now scheduled for death).
There isn't because any serious print shop will laugh you out the door if you come to them with a Publisher file.
Publisher is fine for home/office printing, and you will probably get away with it at your local corner shop that does digital printing on a Xerox box in the back of the shop.
But if you're sending stuff off to the big-boys you will suddenly find yourself needing to adhere to artwork preflight settings, colour profiles, PDF and TAC specs.
Not only will the printer give you validation settings files you can load into Acrobat and Indesign, but if there are issues, the printer's preflight team will be more willing (and able !) to help you if you are using industry-standard tools.
You say this like customers don't show up with a PowerPoint file.
I never really thought about it, but it is kind of odd that the same community that loves using LaTeX for document formatting and typesetting research papers is also using PowerPoint as a desktop publishing substitute.
The real truth is more boring: DTP didn't die at all, it just merged as a category of software with word processors because computers got powerful enough to run programs with a union of their features. Whether the programs in this new combined category got called one thing or the other mainly depended on their history: Word and InDesign today have a lot more in common with each other than either does with programs from the early 1990s that are nominally in their respective categories. Whatever you were saying, it didn't seem to be that, so it was wrong anyway! But I asked nicely because I was curious if there was some substance there.