Asturias56
I would agree with your appraisal of Zanzibar. But that assessment would probably cover most of East Africa. You have to get down to South Africa before you get the type of hotels you get in the destinations you mentioned.
There are some very small relatively boutique hotels/ Lodges with prices to match but not the large developments you get in Seychelles/ Caribbean.
Personally I do like Africa because of that and do prefer it to the destinations you mentioned partly because it’s less developed.
Cheers
Mr Mac