There is no easy answer when it comes to the question of whether or not a blog can be kept private. In theory, it should be possible to create a blog that is only viewable by those who have been specifically invited to view it, but in practice this is often not the case.
Many bloggers publish their blogs openly and make them available to anyone who wishes to read them. This open approach can be beneficial in terms of attracting new readers and promoting the blogger’s work.
However, it can also lead to unwanted attention from third parties who might want to use the blogger’s content for their own ends.
Ultimately, whether or not a blog can be kept private depends on the specific circumstances surrounding it. If the blogger trusts their readers and believes that they will not misuse or distribute their information, then opening up their blog should not present any major problems.