On my opinion this is a critical change in your settings.
In my specific b2B shop, we have daily moderate volumes of new customers and new orders but there are good chances to reach really high volumes soon. But now, this change you have made are influencing our business.
The solution you suggested for B2B is not the right one, please remind that most customers are registering while making their first orders, and anyway we do not have a dedicate person who checks which are the new customers and from where they are ordering.
Please make a fix where we can mass flag which country we do not want to collect VAT, or many of your b2b customers might opt for alternative solutions to shopify