There are always bright spots in every endeavor.
If all you ever did was fly on sunny Saturdays, or only attended Oshkosh and Sun N Fun, you would be forgiven for assuming that general aviation was booming. The facts, sadly, do not support this:
From Wikipedia:
"As of the end of 2015, in the US, there were an estimated 590,039 active certificated pilots. This number has been declining gradually over the past several decades, down from a high of over 827,000 pilots in 1980. There were 702,659 in 1990 and 625,581 in 2000."
That is a 30% decline in pilots during a period when our population grew 28%. A very bad trend, indeed.
Now, if you examine the basics, like average pilot age, avgas sales, aircraft sales, and number of operations, the situation becomes even more bleak. There are many thousands of airplanes that never move, and many thousands of PINOs -- pilots in name only.
We will always have pockets of active GA. Booming Texas areas (Austin and Houston), for example, have thriving GA populations that tend to mask the overall decline. Unfortunately, these don't make up for the massive reduction in actual GA flying overall. Get 200 miles from Austin, and most of the airports are veritable ghost towns.
The bright spots are the experimental homebuilt community, which have attracted many of the remaining active GA pilots (myself included), and unpiloted aviation -- drones -- which are set to outnumber GA pilots as soon as next year.
As for the current uptick in training, that's a reflection of the looming commercial pilot shortage. Will these pilots become active GA pilots on their days off, or just fly for hire? Time will tell.
Bottom line: GA is unhealthy, and continues its decline. Sadly, the only thing keeping our beloved hobby alive are massive federal subsidies -- a situation that cannot last forever.
In the meantime, I will continue to roam the largely empty skies in my RV-8A, enjoying the hell out of GA while I can.