Of course there is some luck, and at times, in the short run, a lot of luck. But backgammon is absolutely, positively, a game of odds, and in the long run, the better you play the odds, the more you will win. The BEST WAY to win a lot is to COMPLETELY FORGET ABOUT LUCK. Don't think about your opponents' good rolls, or your bad ones... it takes your focus and attention away from things you can control - your checker and doubling cube decisions. Yes, there is luck. And I feel the luckiest when I find myself playing against someone who thinks it's all luck.
True, at times, there are several plays that are close, but MOST OF THE TIME THERE IS ONE PLAY THAT IS SUPERIOR to all others. If you have the attitude that there are often several plays you can make, and they're all pretty good or pretty bad, and it doesn't matter much which play you make, then I promise you, you have not learned the game properly. If you take the attitude that several plays are about the same, you will not take the time and care to seek out the best play. On every virtually every play there is a "best" play, and often that play is several percentage points better than any other play. If you give up just 3 or 4% equity on a play (which is less than a "blunder") it's truly not that big a deal, but if you do it just three or four times in one game, you add it up and you've given up a lot of your winning chances. Often what looks like two close plays can turn out to be hugely apart in terms of your odds of winning or losing.
There is no question that Snowie, Jellyfish, and GNUBG are not always right. In fact, there are certain types of positions they consistently get wrong, and there are even positions they will get wrong when you roll them out at length (because they play the moves wrong on the rollouts for these kinds of positions). But overall, the backgammon programs are extremely good, and generally far more accurate than all but a few of the best players in the world. If you are not one of those best players in the world, put your faith in these programs and you will improve your game tremendously.
. I can't tell you how many people I know - even very good players, who believe the computer rolls too many doubles, or rolls just what you don't need at the right time, or just what your opponent needs at the right time. They are wrong. When you are playing on line, the dice are random, and no program has ever been invented that can look at your position and decide, consciously, what roll would hurt you most. As for rolling too many doubles, hundreds of studies have been done, and not just by the owners of the servers, and they have all proven that the dice on line are just as fair and random as dice in real life. People who cry about the dice on line, or live, are simply not "fair-minded" enough to see that they don't roll any better or worse than their opponents. Some people really do roll worse - it's because they play worse. The worse you play, the more bad rolls you are likely to get and the fewer good rolls. That is the definition of playing worse.
It is true that playing experience is essential to improve your game, but you will NEVER be a great, or even "really good" player without study away from the board. There is information in backgammon books and articles that you would NEVER figure out for yourself by playing over the board or on the computer. Great players must learn and know match equity tables and take points and must understand the theories of when to go for the gammon or when to cash, just to name a couple of things you will learn from books. You won't "pick up" these things over the board or even by playing against computer programs like Snowie. If you don't read these things, you could learn them from a coach or teacher. I believe it is possible to become an "intermediate" level player if you are very smart, have excellent math and gaming skills and great instincts, but I HAVE NEVER MET an Open Level player (that is the top level tournaments) that didn't also do quite a bit of reading and study to learn the finer points of the game.