Exactly. Look at GoT, how they botched it even though they allegedly got some pointers on how to finish. Look at Hollywood and how many original movies we got in recent times. I would also stick to reboots and sequels.
My point is, it's difficult to make amazing original stories. Starwars 7-9 was original*, MCU not.
*and naturally, they stuck to known qualities and mirrored 4-6 more or less closely. Another reason why TLJ is the best of the bunch as it was more new ideas.