Obsidian Entertainment's Josh Sawyer kicked off the discussion on social media, when he attributed the death of isometric RPGs to the influence that retailers had on the games industry in the early 2000s. Essentially, Sawyer's point is that retailers would create self-fulfilling prophecies and lower stocks for games in certain genres, thus leading to a lack of sales, rather than the reverse.
"BioWare made Baldur's Gate, which sold well, and [Baldur's Gate 2] sold very well. Black Isle made Icewind Dale, which also sold well, but after BioWare announced Neverwinter Nights, retailers decided that 2D iso games were dead," Sawyer recalls. "Temple of Elemental Evil was the last for a long time."
Sawyer claims that he'd often hear sales representatives "declare a genre/style/look was dead with zero supporting data," leading to reduced stocks in said genre, obviously leading to lower sales. "Truly vibes-based forecasting, which resulted in self-fulfilling prophecies," Sawyer continues.