It’s weird the way the government is on one hand fighting a legal battle to hide the contents of their whatsapp messages during the pandemic, while on the other hand they are fighting a legal battle to expose the content’s of everyone’s whatsapp messages to the law.
It’s not really so much that there is a “tipping point” after which the tech companies will exit Britain, it’s that if you make their product illegal then they have no choice but to stop making it available.
If you make encryption illegal, companies providing encrypted messages apps will obviously have to stop doing so, that isn’t a tipping point, it is the intended effect of the law.