In an ideal world you are of course correct.
In this world data is harvested for profit which leads to spam and an undesirable level of covert surveillance.
For this reason Europe has enacted data protection laws that apply to any data held on European citizens regardless of where the servers are situated.
Names with emails are such data.
Members who wish to converse directly may choose to exchange emails through the existing channels with no special effort on anyone's part.
As you control whether that data is available it is also your legal responsibility to ensure each member has an informed choice on how their data is made available.