There is problem with lots of devices. They can’t by used LAN only. For example, meat thermometer. I wanted somethink like meater. All of them work similarly, thermometer send data over BLE to base station/smartphone which are connected to LAN and send data to cloud. Cloud is sometimes not forced, but without it you can't get data over LAN to more distant devices in some local network as basestation.
But just for using Meater you need (or at least in past needed) cloud account for using it regardles if i you want use only BLE.
I found some french alternative, which has not needed account, but for sending data over LAN it still need cloud. But i wanted access data from home assistant, i wrote them if they can give me protocol so i can read data by some BLE device. I get bullshit response about security. So i scraped idea.
But now i found Combustion inc. It has same approach as french company. Does not need account for using their device, but if you want send data on other device in LAN it go troughs Cloud. But there is one difference for BLE side. They not just gave us protocol. We have their official foss library! So it's best solution I found sofar. Basestatin are used are repeaters for better BLE coverage .