@Robert Hernandez good question, and honestly a really sensible way to think about your power budget — no point running the PA at full tilt when your nodes are basically shouting at each other from across a room.
To answer the core question: there's no automatic adaptive power control happening under the hood on the MultiNav Pro+. The module doesn't dynamically negotiate TX power based on RSSI or link quality the way some higher-layer stacks do — it's not making that decision for you. So yes, if you don't touch it, it's running at max output regardless of whether your peer is 20 meters or 20 kilometers away.
The good news is TX power is something you can control from firmware. The STM32WB07 at the heart of this thing exposes TX power through the HCI layer — specifically `hci_le_set_transmit_power` or you can go through the ACI vendor commands depending on how your firmware stack is configured. If you're using the AI Firmware Builder in the Club, worth describing exactly this use case — something like "set TX power per connection based on whether the node is designated short-range or long-range" — and it'll generate the register-level logic for you rather than you hunting through the ST BLE stack docs manually.
On your data rate question: TX power and PHY data rate are independent. Dropping power won't touch your 2Mbps throughput — that's a PHY-layer setting. You'll just be reducing your link margin, which at 20-30 meters you have an absolutely enormous amount of to spare. You could drop TX power by 15-20 dBm on those close nodes and still have link margin to burn. The tradeoff you'd actually want to watch is that lower TX power does reduce your interference rejection in noisy RF environments, but at that range it's unlikely to matter.
If you can tag your short-range vs long-range nodes in your network topology, managing this from the central controller side is definitely doable — flag the node type during association and set TX power accordingly on connection establishment.
