Analysis of information sources in references of the Wikipedia article "Atari XEGS" in English language version.
The games division [..] saw the home computer division as a threat [..] If any of their new machines could expand into true computers, the reins would automatically be handed over [..] To the games division, this was a fate worse than death [so] they chose death. [..] If, in 1981, the next-generation game machine had been designed to be compatible with the Atari 400 and 800 microcomputers, Atari would not be in the state it is today. Instead, the 5200 game unit was launched. Internally, it was very nearly an Atari 800, and as such was a fabulous game machine. The notable exceptions were that all compatibility and expandability had been designed out [..] with an external keyboard and 800 compatibility, could have been transformed into a product superior to the famed Coleco Adam, way back in 1982.
