That sounds plausible. Or at least it was part of it, because at least Myst would never have sold anywhere near as many units if it didn't look so impressive (in 1993).
Though there is also the simple fact that pure puzzle games can't compete with puzzle+action games (e.g. Zelda), even if the puzzles are somewhat reduced.
You can see a similar thing in movies: Highly successful Pixar movies are typically comedy+action, because mixing in action beats pure comedy in terms of entertainment.
The trend towards action is also present in other genres: Turn
-based strategy games got mostly replaced with real-time strategy games, and turn-based RPGs got replaced with action RPGs where fighting is done in real time.
Though there is also the simple fact that pure puzzle games can't compete with puzzle+action games (e.g. Zelda), even if the puzzles are somewhat reduced.
You can see a similar thing in movies: Highly successful Pixar movies are typically comedy+action, because mixing in action beats pure comedy in terms of entertainment.
The trend towards action is also present in other genres: Turn -based strategy games got mostly replaced with real-time strategy games, and turn-based RPGs got replaced with action RPGs where fighting is done in real time.