Surface Mount Technology (SMT) is the technology of today, but Through Hole (TH) is still an effective method and I can see it hanging in there for a while yet. Through hole is more than a mature technology, it's manufacture is now so well developed that while a market exists, running the machines isn't an economic problem at this time. You will know when the market shrinks - prices will go up.
However, this state of Electronics as a hobby has been discussed elsewhere - and there is one aspect of the nature of electronics that is clear: It is changing.
In the early days, you would build a crystal set - where you actually had a crystal and a cat's whisker which you played around with to get your diode rectification. I still have the rather cumbersome setup my father had in the 1940's. When I was a kid, I bought a crystal set kit - which had a semiconductor diode. No fiddling required. The 'craft' had moved on. Nobody tries rolling their own diodes for this application these days - unless they are doing something retro, nostalgic or educational.
When I was a young lad, ICs were something you had heard about, but would never have expected to have them to play with. Instead, my Philips EE20 kit had discrete components, with the most exotic being an AF114 transistor. DTL and RTL packages were around, but not big in my world. Then things moved on.
The days of the 741, 555 and 7400 series TTL brought a whole new world of capability - and they were embraced with eagerness. The two transistor flip flop was replaced by the far more capable 555 timer in a vast array of applications. Our designs became more adventurous, our objectives more complex and the ability to achieve them far more readily found. Then things moved on ... again.
We now live in a world of electronics where it is commonplace to be able to work with microprocessors, FPGAs and the like which are a scale of capability I could not have imagined 30 years ago, let alone be able to afford. A couple of years ago, I was able to buy 5 Arduino Nano clones for $1.97 each - delivered to my letter box. That level of price, performance and capability is something that would have blown my mind when I was in high school, yet today is commonplace.
So it is with the packaging. We are looking at greater capability which brings greater complexity and the need for space to accommodate it - and since the older TH packages contained so much wasted space on the footprint, package reduction is only natural.
Bottom line ... don't be afraid of SMD. All you need is a steady hand and either good eyesight or a headband magnifier. Don't be afraid to get your hands dirty, it's how you learn.
The days of setting up your own cat's whisker diode for a run-of-the-mill project are long gone.