That's kind of surprising, they seem to be nearly everywhere these days. I remember back when they were rare.
I agree. Komodo dragons are promoted far more than other monitors (Varanus).
According to ZTL,
85 collections have savanna monitors (V exanthematicus)
73 collections have Asian water monitors (V salvator)
58 collections have spiny-tailed monitors (V acanthurus)
44 collections have blue-throated tree monitors (V macraei) and/or green tree monitors (V prasinus)
39 collections have Nile monitors (V niloticus)
38 collections have Komodo dragons (V komodoensis)
23 collections have crocodile monitors (V salvadorii)
22 collections have white-throated monitors (V albogularis)
21 collections have yellow-spotted monitors (V panoptes)
20 collections have Mindanao water monitors (V cumingi)
18 collections have lace monitors (V varius) and/or mangrove monitors (V indicus)
14 collections have black tree monitors (V beccarii)
13 collections have quince monitors (V melinus)
11 collections have Gould's monitors (V gouldii), Timor monitors (V timorensis) and/or Mertens' monitors (V mertensi)
10 collections have long-tailed rock monitors (V glauerti)
9 collections have grey monitors (V griseus)
7 collections have blue-tailed monitors (V doreanus), rough-necked monitors (V rudicollis) and/or Reisinger's tree monitors (V reisingeri)
6 collections have Mitchell's water monitors (V mitchelli) and/or peach-throated monitors (V jobiensis)
5 collections have northern blunt-spined monitors (V primordius)
4 collections have Gillen's pygmy mulgas (V gilleni), Gray's monitors (V olivaceus) and/or freckled monitors (V tristis)
3 collections have Dumeril's monitors (V dumerilii) and/or northern Pilbara rock monitors (V pilbarensis)
2 collections have Biak tree monitors(V kordensis), tri-coloured monitors (V yuwonoi), ornate monitors (V ornatus), New Guinea spotted tree monitors (V similis) and/or Bengal monitors (V bengalensis)
1 collection has Auffenberg's monitors (V auffenbergi), Yemen monitors (V yemenensis), turquoise monitors (V caeruliverens), Spencer's monitors (V spenceri), Rainer Gunther's monitors (V rainerguentheri), pygmy rock monitors (V kingorum), line-tailed pygmy monitors (V caudolineatus), Negos water monitors (V nuchalis) and/or giant monitors (V giganteus)