But "When people invest" - This isn't investment behavior. This is speculation and most likely simple addiction to gambling behavior they drive and incent people to do.
It depends :-)
Some seem to have a fall-back or fail-safe that isn't overwritten. Even with flashing known firmware, the reliability of the little guys was questionable. Random lockups and very touchy to power source.
The quality and consistency of firmware/functionality/hidden stuff on the various 8266's I have leads me to avoid them. I had a pair that phoned home to some Chinese domain and registered all via HTTP, and a quick Wireshark yielded it phoned home for commands. Not on my network...
You can pick them up cheaper on ebay, as well.
State files should be considered secret....