Speaking of the effect of GDPR and pandemic...
One publisher I know in a western European country informs me that witnessing is carried out strictly by email. No physically mailed letters, no phone calls (except to family members who don't mind being harangued about "the truth" on a weekly basis).
A consortium of congregations have arranged a sort of "clearinghouse" for emails addressed to hospitals and rehabilitation facilities. Emails can be "addressed" to "patients" or "medical staff".
The actual emails with the witnessing message are sent to a central email address. A group of "approved" JWs with access to that email address inbox review the emails sent, and then forwards them to actual hospital / patient / doctor email addresses that they and only they have.
The net result is, witnessing is reduced to writing impersonal emails addressed to "Dear neighbor" or "Dear doctor" and sent to a "black hole" where the email is later distributed [somewhere]. There is no feedback to the JW email writer, no chance to "cultivate interest", no ability to make return visits, nothing. Just write an email, send the email, write another email, send the email, ad infinitum.
It is of course a completely unsustainable model. Eventually, the return visits that JWs had pre-pandemic will get tired of weekly phone calls, or they will study and become JWs, and there won't be anyone with any RVs or studies to do.
