With Always On Display, your iPhone 14 Pro or later pro-model iPhone will dim the Lock Screen while still showing information, such as the time, widgets and wallpaper, all while using new technologies that make the display power efficient.
There is likely to be no utility to this feature for blind and some low vision users, so in this episode Thomas Domville shows us how to disable it.
To disable Always On Display, go to Settings > Display & Brightness > Always On Display, and double-tap the "Always On Display" switch. This Apple support page provides more information on Using Always-On display with your pro-model iPhone.