GIF was created by Compuserve in 1987 for their BBS-like service, so they had a captive user base. Their previous image standard was black and white -- 8-bit color was a new thing. JPEG was created by an international standards group to handle photographs, and I get the impression it came along about as soon as computers could handle it. I couldn't find any earlier (pre-1992) lossy color image formats. PNG was developed in 1995, within a year of Unisys announcing that it was going to enforce patents on the LZW compression used in GIFs, and even then it took many years and some bad publicity for Unisys before PNG really caught on.
GIF and JPEG were the first major color image formats of their type, and they were created about as early as possible. PNG was created in response to the limitations of GIF's patent status and 8-bit color, and was adopted much more slowly. I don't see a new image format catching on without a compelling reason, and historically, improvements in compression have not been enough. A reasonably high-quality, high-resolution image is just not that big.
By comparison, new video formats come along more frequently due to the large and increasing bandwidth requirements of high-quality streaming video, with early adoption coming from pirates, anime fansubbers, and other tech-savvy user bases.