I would say non of your points are valid, but I am someone with about 300h in Starfield and I didn’t quit because I didn’t had any fun anymore but because other games stated to pile up. Personally I can’t wait for Shattered Space and I will play most likely start a complete new character and play the game from scratch with the DLC.
Do I think that it is a perfect game? Hell no! No game is perfect and Starfield has its fair share of problems and issues (the really boring temple “puzzles” for example). But for me Starfield is a very interesting and believable hard science fiction world that is not far away from what we could do with our technology now, if we would figure out a way to jump faster then light. Starfield is very good in delivering a believable space, and yes a believable space is huge and mostly boring. But that doesn’t mean that you can’t find for example beautiful places out there, it just is random, take lots of time (due to the frigging size of space and planets) and is rare. Starfield gives us a universe that is in huge parts like the real universe out there. For me the main quest of Starfield is one of the best main quests ever written by Bethesda, just after Morrowind and way better then the “Find the hidden heir, protect the hidden heir, close some portals and watch the hidden heir fight the big evil of the game” main quest of Oblivion. That I, personally, find utterly boring and unsatisfying. The strengh of every Bethesda Elder Scrolls/Fallout/Starfield Game is not that the main quest but all the other quests around and starfield has lots of great side quests, companion quests, and faction quests all over the game.
Is Starfield a 9 or 10 out of 10? No! But there are only very few games out there that I would give a 10/10 rating Is it a 1 out of 10? Not at all! But it is a strong 8 and could become a 9 when the DLC is for Starfield what Far Harbour was for Fallout 4.
All personal taste, Starfield is unfortunately not the right game for you but it is a great game for me. I love it!