I left an Ecobee smart thermostat when I sold my house. I deleted my online account and you could still adjust the temperature manually. I assume the new owner

I left an Ecobee smart thermostat when I sold my house. I deleted my online account and you could still adjust the temperature manually. I assume the new owner would eventually set up an online account but they wouldn't need to if they just wanted a 'dumb' thermostat. The Ecobee also works as a 'dumb' fallback when wifi is down.