BLE should also work but you also want a dongle, so hardware wise it’s the same; ideally you also want a couple gateways (Shelly devices can do that out of the box btw, and new Shellies will be supporting Zigbee.)
Yup, you're right -- looks like zigbee2mqtt is a huge unlock, hard to build without it since it supports so many things!
Not excited about having to essentially now also bring along a MQTT broker but... It's probably pretty painless to run most brokers and it's likely a single-machine-is-fine affair.
You should look into zigbee2mqtt IMHO.