It's Netflix' own fault that everyone is rotting for Hulu to pick up their shows. Canceling shows after three seasons and basically throwing a tantrum when Disney announced Disney+. Then again Daredevil and Jessica Jones were at the three seasons limit anyway, but that's no reason to cancel Luke Cage over "creative differences."

Tumblr lost so much of its users and value over time.

Marvel planned the MCU very carefully while others (including DC) just wanted the same thing, conjured out of thin air. Harry Potter and LotR are few of the successful franchises. The Harry Potter movies had the support of an entire generation growing up on these books behind them. Percy Jackson (which I never read) failed and I'm not sure what to make of Artemis Fowl getting adapted after all these years.

I can see Fantastic Beast going down that same road as other book franchise (even though there are no books to back this up). The third movie still getting made and then it kind of petering out.