At least in EU, WiMax failed because the states decided to licence the spectrum to the usual telcos that had no interest in deploying the technology fearing a possible cannibalization of their own businesses.

However, WiMax is not a mesh network, although you can obviously use WiMax as a physical link on top of which a mesh protocol can work.

I suppose it's time we have a public open hardware effort in order to break the telcos' unhealthy monopoly.

Because the hardware and software was expensive and 3GPP ended up putting out a spec (LTE) that understood the way to move forward was to work with existing infrastructure and expand from there.

Sprint/Clearwire have deployed WiMax to >70 U.S. markets covering over 100m residents. If you live in e.g. Atlanta, you can buy a WiMax connection today. See clear.com.