This happened to me. I developed a computer vision technique that achieved a well known result but without the same constraints. Although it never surpassed the other technique for most images, it worked in a wide variety of cases that the previous technique did not.

My major professor diluted the paper and added other content consistent with the previous method. Not just adding prior art to the introduction, but changing the meat of the paper so that it didn't seem like a departure.

He assured me that this would make it easier to publish, and publishing was all that mattered. There were no bonus points for publishing a novel technique, and there would certainly be extra work having to deal with referees.

I'm very glad to be out of that environment now. I noped out of academia and happily dealing with corporate B.S.