My honest opinion that either you had a source content issue and/or a faulty set. I'm still not sure why you didn't get a replacement, at least then you would have been sure it was the source and not a faulty set or you might have got a great set and be sat there being able to make the most of all the UHD/HDR content as well. My first ever "proper" television was a SONY 36" CRT and the first two were awful, but the third was absolutely superb and it lasted me for many years. Like I say, your experience isn't representative of owning this set. I hope you find one that meets your requirements.No opinion is factual regarding reviews, as we all see visuals differently, and have different perceptions/justifications - therefore all views are valid.
Even the inferior sets get a high 4.5+ rating on the Sony's website, so they cannot be taken as gospel either, as we know. The set I also sent back before the 9505 has a 4.7+ rating out of 160 reviews.
There are 55" 4K TVs on Argos (Hitatchi) for £360 with over a thousand reviews, showing 5 stars, and I'd assume you wouldn't buy one, so it's all relative to justifying the expense from the purchaser.
And regarding my new set, it is a temporary set until something comes along that I feel actually worth the money. It may not sound like it amongst my posts, but I very much wanted that set to be the 9505 that was returned this morning (excellent service from RS, I must highlight..)