I know this is from several pages back, but I just couldn't let it slide
That's simply not true. The trend of building non-IP attractions remained strong throughout the mid-80's, and continued on into the late-90's. More than anything, this reflects the lack of major development of any kind at DL for the last 40-ish years, since it's essentially a mature park. There are still occasional additions here and there, but parkwide more things have stayed the same than changed since 1979
Here's a list of attractions (excluding entertainment and meet & greets) that have opened since 1979. Surprisingly, the number of IP-focused and non-IP-focused additions in that period is nearly the same, though the trends have certainly shifted in recent years
Non-IP:
- Magic Journeys (1984)
- Videopolis (1985)
- Big Thunder Ranch (1986)
- Captain EO (1986)
- Jolly Trolley (1993)
- Innoventions (1998)
- Rocket Rods (1998)
Questionably "New", non-IP:
- Wonders of China (1984)
- American Journeys (1984)
- Country Bear Christmas Special (1984)
- Country Bear Vacation Hoedown (1986)
- it's a small world holiday (1997)
- Tomorrowland '98
- Astro Orbitor (1998)
- Autopia rebuild (2000)
- Great Moments with Mr. Lincoln (haircut version) (2001)
- Space Mountain rebuild (2005)
- The Disneyland Story (2005)
- Great Moments with Mr. Lincoln (Hall of Presidents lite version) (2009)
IP-driven:
- Pinocchio's Daring Journey (1983)
- Star Tours (1987)
- Splash Mountain (1989)
- Mickey's Toontown (1993)
- Gadget's Go-Coaster (1993)
- Roger Rabbit's Cartoon Spin (1994)
- Indiana Jones Adventure (1995)
- Honey, I Shrunk the Audience (1998)
- The Many Adventures of Winnie the Pooh (2003)
- Buzz Lightyear Astro Blasters (2005)
Questionably "New", IP driven:
- Fantasyland 1983
- Tarzan's Treehouse (1999)
- Haunted Mansion Holiday (2001)
- Finding Nemo Submarine Voyage (2007)
- Pirates Lair on Tom Sawyer Island (2007)
- Sleeping Beauty Castle Walkthrough (2008)
- Star Tours (2011)
It's also worth considering the attractions that have closed in this era have been overwhelmingly non-IP focused, which skews the overall balance of what remains toward IPs more than considering only the additions.
It's also far too easy to gloss over DCA, which only had about 20% of its opening day attractions IP-driven in 2001 (though today it's over 80%). Given when the trends started to really shift (both at DLR and Disney parks worldwide), I can't help but think that management learned the wrong lesson from DCA's (and WDSP's) failures, focusing almost entirely on inserting familiar characters as a shortcut for building quality and worthwhile experiences.