I feel like productivity increase stopped at 1080p-1440p@60 for most office work, 4k was diminishing return point for art work. Extra real estate / pixel density hasn't added much to the process, maybe 5k for video people who want to work in 4k. There's some peole with sufficient visually acuity that "feels" better working with more density and refresh rate, but it's hard to rationalize the cost on performance grounds now.