They exist: https://www.viewsonic.com/us/vx1655-4k-oled-15-6-uhd-oled-portable-monitor-with-60w-usb-c-and-mini-hdmi.html?utm_source=google&utm_medium=cpc&utm_c

They exist: https://www.viewsonic.com/us/vx1655-4k-oled-15-6-uhd-oled-portable-monitor-with-60w-usb-c-and-mini-hdmi.html?utm_source=google&utm_medium=cpc&utm_campaign=Google_Consumer_PerformanceMax_PortableMonitors_Purchases&utm_term=&gad_source=1&gclid=Cj0KCQiA4fi7BhC5ARIsAEV1Yibg4e_ywkE53osQDm5qTdU-VN29px844Bge5T86qvgP4eqnEW6ZgogaAvopEALw_wcB https://www.viewsonic.com/us/vx1655-4k-oled-15-6-uhd-oled-po... But there are so many off brands, and ViewSonic is sort of a step below what I usually go for. Here is one from LG that is not quite 4K but still better than 1080P: https://www.bhphotovideo.com/c/product/1766952-REG/lg_16mr70_adsu1_16_gram_view_ips.html/?ap=y&ap=y&smp=y&smp=y&store=420&lsft=BI%3A514&gad_source=1&gclid=Cj0KCQiA4fi7BhC5ARIsAEV1YiaVdBrgk71sd_Q07rUF4nWtfU6dVvPcnGFHOXvqsepQgLMEP7g-fkQaAuIsEALw_wcB https://www.bhphotovideo.com/c/product/1766952-REG/lg_16mr70...