There's a fairly wide history of self hosted Government Microsoft Exchange servers ending in ransomware payouts that suggests that blunt self hosting rules isn't as useful as it sounds.
And right now you look can look all the big MoveIT mass exfiltration hitting a wide range of orgs that wouldn't use Sharepoint "for security reasons".
In India, anybody can get a business account, which allows you to setup a catalogue of things, services, and you can pay inside app through underlying UPI interface (government operated quick guaranteed no-return money transfer). I have booked cars for rental, I have bought grocery, pizza, shoes n stuff.
WhatsApp was used by the Afghan Army to coordinate military communications and maneuvers. I wouldn't be surprised if other under-resourced military forces (i.e. Ukrainian) use it as a form of communications.
Afhanistan and the Ukraine both have a little less than 40M inhabitants. (Which is around half of germany, or like 20M less than France).
The Ukraine has/had a relevant IT-offshoring sector, from Wikipedia there's around 1/3 of the soviet military industry that was sitting there (including companies like Antonow)... and they had a few years of preparation since the krim was occupied where they knew that russian secret services would try to undermine any kind of communication infrastructure.
I doubt that they currently rely on WhatsApp for military communication...
