This is at least apparent for what I'm observing in my country on the Southern tip of Africa. The reason seems to be that VarAC provides most of the functions that JS8Call already provides (apart from the open source), and then provides a lot of usability improvements as well as transmitting images, documents, faster speed, VMails, etc.

I've been getting up to speed with it the last two days, and am really enjoying using it. I've documenting what it is about, how it compares with JS8Call, and some tips I've been learning, at the web page I've linked to in this post.

See my experiences to date at https://gadgeteer.co.za/hamradio/varac-p2p-digital-mode-chatting-application/