Is public by default an unsafe default?

[NotYouAgain]

No doubt this will create controversy too.. why.. I don't know... 
but anyway....

Declarations within a D module (other than import declarations) 
are public by default.
This includes public by default in a class too btw.

Programmers from many of the other major languages will have to 
deal with this surprise (in addition to the surprise of how 
private has taken on a completely new meaning in D).

Not discussing private here! We all know what will happen if we 
do. So don't!

Question 1 - is 'public by default' a sensible default for a 
language that is aiming to be safe by default?

Here's an interesting article relating to Kotlin, where I believe 
public is also the default. It kinda sets the stage....

https://discuss.kotlinlang.org/t/kotlins-default-visibility-should-be-internal/1400

Question 2 - if public is not a sensible default for a language 
that is aiming to be safe by default, is it too late to change it?

Question 3 - if a change was made, what would become the new 
default?

Please be respectful in your comments, if you have anything to 
say.