I think one of the main reasons for Sony doing this is the lack of content in this realm. Movies, at 24fps, can pass at the Sony bandwidth.
As remains the case, there is no 'perfect' projector out there yet. But, every year, it seems that we are getting just a bit closer. Sony will get on board with 18Gb/s connections soon enough, and their TVs remain well respected in the industry. So, they have 18Gb/s capability, and they will get it into the projectors, and we will see prices drop, and things improve, etc., etc.
The Sony HW45ES hasn't been upgraded in a couple of years now. By most accounts, it remains the absolute best image you can get under $2,000. I would buy one over everything out there under $3,000 today. In fact, the next step up from that would be a JVC.
Projectors simply aren't TVs, They aren't as bright, and they never will be. They have issues creating huge contrast ranges within a single shot, and their dynamic contrast is something that I find visually distracting.
Since film is not shot to Rec 2020 but DCI P3 (I believe I may be quoting this not quite right), so at this point, Sony really focuses (pun!) on hitting the same colorspace that theaters and digital cinema uses. They don't strive to hit what gaming consoles can achieve at the highest end.
This isn't a long term 'perfect' solution, but since projector junkies often upgrade every five years or so, it's the right solution for right now to get the best possible image on screen for a home movie theater. JVC often follows the same approach, but JVC with their 5th generation 4k products has had more time in this arena. I wish JVC would compete with Sony under $2,000, but between the HW45ES and the 285ES, there is JVC sitting there and tons of people buying, which would include me if budget allowed.
I want to point out that about 17 years ago I had a 120 pound projector hanging from the ceiling in my family room. It was one-tenth as bright as what I have today and never was as sharp. Just a reminder that we've come a really long way in a fairly short time span.