Over the years, a variety of companies jumped into the fray, including Gravis, Media Vision, Diamond Multimedia, and many more. I pretty much experimented with all of them, but the standard as defined by Creative's Sound Blaster line meant most of the cards had to follow the standard. The alternative to Sound Blaster with an incredible following was Gravis, with its Ultrasound series of cards. But my experience with Gravis cards was, shall we say, less than optimal. And that's being charitable.
Given Moore's law and the increasingly large transistor counts available to chip designers, it was inevitable that audio would be integrated into core logic. Chipsets were the logical place for further integration, and if you could integrate Ethernet and even graphics, why not audio?