I'll always have a soft spot for Atari, despite all of the turmoil over the years regarding the brand.
The 7800 would have been a welcome redemption following the lackluster 5200; however, the crash of 1983 and internal company struggles made them decide to shelve the 1984 release of the 7800.
By the time they chose to jump back into the market by pulling these out of the warehouses and getting them on the shelves in 1986, the stigma of the brand was still somewhat fresh, the hardware was out-of-date, and Nintendo was well on their way to devouring the majority of the US market with the NES.