Almost no 4k monitors would be considered high dpi. To achieve 220dpi you need a 4k monitor to be 20 inches. 27 inch 4k monitor 4:1 pixel mapping makes it appea

Almost no 4k monitors would be considered high dpi. To achieve 220dpi you need a 4k monitor to be 20 inches. 27 inch 4k monitor 4:1 pixel mapping makes it appear to be 1080p, which many people would not consider to be appropriate for that size monitor. You can use fractional scaling but that comes with its own sets of issues because the pixels don't map correctly. 27 inch 1440p at 100% scaling in Windows or MacOS is what most would be consider appropriate sizing for UI elements and text by default, so in order to achieve high dpi you need a 5k monitor, like the LG UltraFine or the 27 inch iMac.