Strength multiplies technique. If you have only strength and no technique, then it doesn't matter how strong you are. If you have only technique and no strength, it doesn't matter how good you are. You're probably not going to win much.
With that said, being stronger does tend to lead to people cutting corners in training, often unintentionally. If you are stronger than your training partners, you can often succeed against them by using strength instead of technique. Your success reinforces that your technique is "correct", so you don't see much reason to improve it.
As an example, let's use the above formula. Strength multiplies technique. If you need an 8 in order to be successful, and you have 3 strength and 3 technique, then you have 9 technique and will succeed. If you have 5 strength, you only need 2 technique to succeed, and so you will convince yourself that your technique is good, because it succeeded, even though it is worse than the other person.
In order to fix this, one must consciously assess themselves whether they're using strength or technique, and when technique can be improved even if they already succeeded with it. Then you run into the other problem, which is adding strength back in, when you've built a habit of keeping it in reserve.
There is another aspect. I see this question on reddit every once in a while: "If a bigger/stronger person will beat a smaller/weaker person, what is the point of training martial arts?" You'll see any art that includes grappling (everything from aikido to BJJ) will claim to work on bigger, stronger opponents. The reality is that it's going to be very difficult, especially if they have any idea how to fight. But we also don't want to discourage people from training. I think there's a fine line between being realistic and turning people away.