Later came the digital circuits and microcontrollers, which required one to learn assembly language.
Nowadays is the time for SMT components, and worse, for the fine pitch or leadless components, some of which I believe are the work of the devil.
The point I am attempting to drive is that, thorough these past 50 years I have had to adapt. Do I always like it? Do I enjoy that any DSP can provide a much better filtering function, than anything I could ever accomplish with opamps? No, many times the answer is not really. But I recognize that the world has moved on.
In which case, is there any point for a new beginner to even try to progress beyond what circuits can be achieved on a breadboard with passives and a 555? It feels impossible for anything you can do with circuitry to be better than the software domain. So a dev board furfills all the needs.
Even
if we're at the point where you can put together "hats" like LEGO® bricks, that's never going to be as "tidy" — or as
small — as a custom PCB. It probably won't be as cheap or as robust, either. Besides, there are projects for which an MCU is overkill... and speaking of "robust", for some of the projects I'm tinkering with I specifically
don't want an MCU because it's so many more things that can go wrong. Then there are projects for which there
isn't a pre-built module (at least, not one that isn't
prohibitively expensive). None of which considers that the whole point of a
hobby is to have fun.
I don't think THT is "dead". I
especially believe that hobby PCB design isn't dead; in fact, the proliferation of low-cost prototyping outfits suggests just the opposite! I'm willing to consider that if one wants to "try to progress beyond what circuits can be achieved on a breadboard with passives and a 555", one may be hard pressed to avoid dipping one's toe into the SMD pool, but so far I've sketched out several projects that haven't required any components
not available as THT on boards
I build. (To be fair, some of those use
pre-built Arduino boards that use SMD, and one wasn't really practical in the size constraints I had without resorting to SMD, but the point is, leaving aside that one size-constrained issue, I could build all of those projects without ever soldering a single SMD component myself.)
...and some serious hard-core folks still build projects using vacuum tubes. The hobby scene
is not the consumer goods scene.