Well, to the OP (sorry, I don't know your name.), I'll offer a contrasting opinion of our industry.
I, for one, am extremely thankful we got into hardscape so many years ago. Like you, there was a time when I had no clue how to do hardscape work, much less sell it, make profit at it, and make sure it was done well. But we learned slowly over time and our skills have improved over time. I'm thankful because it's been one of the most profitable parts of our company over the last several years. Pavers, in particular, are getting a LOT more popular around here. But despite that, there are still not a lot of companies in our area who can really do nice, custom paver patios, driveways, pathways, etc. I see competitors work all the time. Often it's a plain, perfectly rectangular patio, the pathways are plain and straight, with no curves or dimension. There often aren't any additions to the patio (e.g. seat wall, fire pit, lighting accents, built-in BBQ, etc.). There's plenty of guys around here who can do that stuff and have decent photos of that kind of stuff. But guys who can do paver work that involves beautiful curves, accentuated borders, multiple levels, steps, more creative shapes, nice winding pathways, and some added features to the patio too - there aren't nearly as many hardscape guys like that around town. So those of us around here who can do stuff like and are good at marketing ourselves can charge a lot more for our work. It actually is very profitable, most of the time.
It's also very rewarding. Especially as you grow and every once in a while do something that is even more challenging and specialized than what you've done to date. It's very rewarding from taking someone's yard from a mud pit of soggy grass and turn it into a whole outdoor living space that is beautiful and functional, that's very gratifying. I don't know that I've ever got to the end of a job like that and not had the customer just totally thrilled when we were done.
It's also nice compared to other kinds of landscaping in that if you do it well, there are little to no call-backs. There's nothing to die. Nothing that needs watering. Nothing that needs cut, fertilized, or weeded to stay looking nice. It's easy to maintain and stays put without too much extra effort. And people love you when you are done. We also get more referrals for our hardscape work than just about any other variety of landscaping that we do.
Is it challenging sometimes to find good workers? That depends a lot on your area, honestly. In some places that's probably a lot more true than others. I wouldn't say it's super easy to find good, reliable workers. In my area I'd say it's moderately difficult. But it hasn't been that big of a challenge. In other areas, maybe it is more of a challenge. Nonetheless, there are thousands of companies around the U.S. and Canada who do find ways to get that taken care of and keep the employees around once they find them. My foreman on our top 3 install crews have all been with me now for 10 years. They do good work and we reward them well. The helpers may change from time to time but it hasn't been too difficult. It's a lot easier to find workers for this side of the business than it is for the maintenance side, that's for sure.
Profit margins are low??? Are you kidding me? Try running several lawn care crews. That side of the business is WAY less profitable than hardscaping is. This is one reason why I think a lot of LCOs find hardscaping to be a good thing to branch out into. Because if you've found a way to make profit doing weekly lawn care and clean-ups, you will find hardscaping to be MUCH more profitable than that. I think it's a good business to segue into, if you're already in the green industry.
Hardscaping is also nice, compared to the other sides of our industry, because workers are happier doing this kind of work. I find the workers like landscape construction and hardscaping a lot more than they do weekly lawn care. A lot of my installers came from the maintenance side of our company...moved over to our enhancement crew (which does light landscaping and hardscape jobs) and then a year or two later, eventually over to our install crews, which do the more challenging landscape and hardscape installation jobs. The construction side of the company pays more per hour than the other sides do and it's something most of the workers aspire to working in. There's a little more pride that the workers take and receive from that kind of work.
I agree with DVS that it does take really good people skills, good sales and presentation skills, good marketing savvy, good money management skills, etc. If you're not better at that than most of your competitors, then yah, probably not a good business to get into. But I don't think any of that is unique to hardscaping. It applies to almost any other kind of construction work too. Most contractors in general go under over time - not just hardscape guys. Being a contractor in general is challenging and requires constant improvement, diligence, and exemplary money management, very good employee management, great and cost effective marketing, etc. Hardscaping is not much different than any other kind of construction. But I don't think it's any worse.
I believe if we hadn't branched out into other things like Hardscaping and Outdoor Lighting, our company would have never been nearly as successful as we are today. I may have even had to fold up shop a few times, as tough as things got. Fortunately, the money we were making in the install side of our company (a big portion of which is hardscaping) really helped keep us profitable in difficult times. And it's still the item that brings in the most money each year out of all the different kinds of landscaping that we do.
So I'd encourage you to look into it. Just go slow. Don't be too ambitious and be willing to learn. Don't take on medium jobs until you've done a ton of small jobs. Don't take on large jobs until you've done a ton of medium jobs. Don't try to take on too many different kinds of hardscaping all at once either. Like I said before in this thread, you can make good money just subbing out work that you don't do and doing the rest. Do that for a while until you learn more. Good luck!