What surprises me the most is the 1GB option is even viable though I can imagine this will be for IoT users who shove Pi's into things doing embedded stuff where a kernel with a few user space things along with maybe a container are doing all the work.
Well to be honest, I'm doing just fine with my 1 GB Pi3B home server. Sure, another gigabyte wouldn't hurt, but I'm able to run influxd, zigbee2mqtt, telegraf, grafana, homeassistant (containerized), mpd and navidrome on it without issues.