Have you tried the Reticulum network? https://reticulum.network
I have been meaning to try it out
I agree with you, Meshstatic is not really reliable in this situation.
But you need to consider couple of issues: the power for a Lora node must be maximum 0.1W, compared to 0.5W of the free PMR446 handelds.
Moreover the handelds are using FM that is not really efficient in term of power, while a Lora node can be powered easily with solar panels.
Even with a YAGI or a dedicated pole antenna, both tuned to 868 MHz, the range in my location is quite poor. The signal seems to drop off quickly, even after walking just a kilometer down the road. While I understand that height is key (and my antennas are fairly high), it appears that 868 MHz attenuates very rapidly.
So, to reiterate, I don't believe Meshtastic is a particularly effective solution. The principle behind it is sound, but the practical execution falls short. I think established methods like Hamnet and traditional amateur radio are far superior, especially now with SDRs making a simple handheld radio incredibly affordable (around €20)