Because the franchise deserves better.
The franchise has suffered a lot worse than TFA and Rogue One.
I'd honestly argue there are only two truly great Star Wars movies. Within the much revered Original Trilogy there is a (in my opinion) stark outlier in Return of the Jedi. It's HF so I'll engage in my own opinion of tiering all the canon Star Wars entries
Excellent
Empire Strikes Back
Great
A New Hope
The Clone Wars (show)
Pretty Good
Return of the Jedi/The Force Awakens (I have them even)
Decent to mediocre
Star Wars Rebels
Rogue One
Crap
Revenge of the Sith
The Clone Wars (CG film that had a cinematic run)
Garbage
Attack of the Clones
The Phantom Menace
(for all the godawful dialogue, AotC still has a better core story than TPM and better action. The score of TPM is marginally better and the larger use of practical sets is more aesthetically pleasing but it doesn't reconcile the fact that it's a useless narrative, a boring narrative, and it makes the viewer suffer Jar Jar and toddler Anakin)
So...if you're holding Star Wars to this standard that it ought to be handled by the few remaining auteurs of the industry or not at all, well...I would've given up a long time ago. Luckily I grew up as the prequels were being released so I can only look up from there and view episodes 4 and 5 as pinnacles and not the running standard that is all of a sudden being besmirched. It's entertaining and sometimes dumb sci fi fantasy built within a fictional universe that draws people in. Even Peter Jackson couldn't recapture the magic of The Lord of the Rings with his pitiable Hobbit films. You can choose to have fun with it or bemoan the fact that Disney wants to play it safe with their investment. I personally don't find it hard to derive enjoyment from the better Star Wars films and show.