The Digital-Based Operational Transconductance Amplifier (DB-OTA) has been proposed in 2013 aiming to the systematic, scaling-friendly fully-digital implementation of traditional analog functions in integrated circuits. The DB-OTA concept and its evolution over the last ten years is summarized and analyzed in this Letter, starting from the first proof-of-concept prototype based on off-the-shelf components up to the most recent time-evolving variants, highlighting the potential of this approach in satisfying the ultra-compact area, ultra-low voltage and ultra-low power required by energy autonomous Internet of Things (IoT) sensor nodes and next-generation biosensing. Perspectives of this technology will be finally delineated.