3rd world country carriers likely don't want to pay licensing fees and/or don't have the influence to get CDMA phones made for them like Verizon and Sprint can. They also don't have the huge numbers that the US has.
How does that constitute GSM as being superior? Better yet - could you explain to me how CDMA is such a dying tech (ignoring the fact that Verizon & Sprint will be using it as a fallback for years to come), when GSM is older and also will be replaced? LTE is a big migration for both GSM and CDMA carriers. There's very little related between either of them to consider GSM thriving.
Actually we did. The carrier according to some report had huge benefits and profits. Small countries might surprise you.
LTE was never for CDMA upgrade... Wi-Max is. Verizon is jumping over to LTE because they feel will allow them to do what GSM allows AT&T to do thru HSPA, faster speeds and better features (simultaneous voice/surf).