Nyerere or Tanzania not being popular in western countries is due to obvious reasons.I've seen many American girls named Kenya and a bunch of black people in the western world named Kenyatta .Isitoshe pia kule Disneyland kuna train station inaitwa "Nairobi Railway station' . For our Tzedian competitors i've never seen Americans naming themselves Nyerere au train station named Dar station.
Since independence, Nyerere never entertained western countries nor did he even share or follow their political view. Worse still his government supported liberation efforts in many African countries till they achieved their liberation. All this added to their hatred against him (maybe and the country too). Moreover, Nyerere was openly vocal against their capitalistic view and the like.
Western countries (particular on those times) almost always never make anybody popular on those grounds
Secondly,names to be used into other countries,I do not see how is that so special. At least, what is so special with the person who use those names in the first place!?
And,Jamaica,despite the fact that I love reggae music,I do not see anything more special from there other than the popularity of opium and opium legalization efforts by many of their musicians.
So, whoever take pride in Jamaican using their names, all the best and hopeful it will add something to them.