I worked at a software store when Myst came out, and we sold MOUNTAINS of it. That at the 7th Guest (and Encarta, LOL) were the go-tos when people added a CD-ROM to their system and wanted something to do with it. But the feedback was universal - after a couple hours in Myst and the visual excitement wore off, it turned out there wasn't much game. It wasn't much more than a graphic Choose Your Own Adventure book.
Doom came out shortly later, and everyone forgot entirely about Myst. We sold mountains of Doom, and then we sold mountains of those *terrible* compilation CDs that had bazillions of maps downloaded off the internet. And then Doom2, and then more add-on maps (and not long after we started selling NICs and 10Base2 terminators ;). Being able to go anywhere and engage anything was what Myst didn't do, a step we had *expected* Riven to take... but it didn't.
Under a Killing Moon was also a big seller - and there were other games in the vein, too. All very interesting to play, but like the LucasFilm-style games they got murdered by FPSs and RTSs. I never quite understood why - Day of the Tentacle and Monkey Island were great games with broad appeal. Strange they didn't survive longer.
heck.. what I want the answer to is what the fuck happened to space combat, and the X-Wing & Wing Commander promises of good games!