Upgrading from Sony VPL-VW675ES..juice worth the squeeze?

I'm going to guess that when your lamp was fresh, you were getting perhaps 18 fL on a screen that large, for 100% white. With over 3000 hours on the projection lamp, you are undoubtedly down to 9 fL for 100% white. You do not mention whether your projector is 1080p or 4096p but either way, yes, projectors have come a long way. But unless you are willing to spend $20K or more for a projector with a laser-phosphor illumination system, you won't see all that much of an improvement. UHD/HDR is a revolution in video. But projection is so compromised by low peak white levels, it can't compete with flat panel TVs. The brightest projector I've ever experienced (I get to use a LOT of projectors for a month or two at a time) produced about 75 fL on an 82-inch wide 1.0 gain screen. On a 123 inch screen, that would be knocked down to maybe 40 fL, possibly even 35 fL. 4K UHD/HDR Blu-ray discs are mastered at either 1000-12000 nits (about 340 fL) or 4000 nits (almost 1200 fL). All that extra light is used to enhance images with a wider range of colors and bright highlight reflections. The less-bright the playback device, the less great UHD/HDR looks. With an excellent 85-inch diagonal flat panel TV sells for not much more than $3000 and it will reach 3000 nits for peak white (almost 1000 fL) and has almost 800 local dimming zones, it's pretty hard to say a $20,000 projector is "better". You can get the same cinematic experience from sitting 8 feet from an 85-inch flat-screen TV compared to sitting 12-feet +/- from a 120-odd-inch projection screen. It is my industry pro opinion that projection in movie theaters will all but disappear in the next 10 years to be replaced with direct-view LED screens that will be FAR brighter than any projection system can hope to be. Currently, large flat-screen TVs outperform any movie theater using projection if you use a 4K UHD Blu-ray-quality source. That is forcing movie theaters to look beyond projection. There are already some theaters using direct-view LED movie screens... it's only going to grow.