[bipson]

IIRC in its initial version it was never "mesh", but more like fixed multi-hop routes over one or two intermediate nodes (i.e. no route discovery)

[dromtrund]

This is true, but this was never really a problem for the adoption. Spec delays, no firmware upgrade support, and most importantly no proper backing by phone or gateway vendors. Thread and matter seem to have fumbled their opportunity though, so it might not be too late.