DESQview/X sucked the wind out of DESQview's sails. It was, on paper, a massive upgrade. I had been running DESQview for years, with a dial-up BBS in the background.
But you couldn't actually buy /X. After trying to buy a copy, my publisher even contacted DESQ's marketing people to get a copy for me, and they wouldn't turn one over. Supposedly there were some copies actually sold, but too few, too late, and then /X was dropped. There was at least one more release of plain DESQview after that, but by then Windows was eating its lunch.