Do people that were abused have attachment issues?  The question really needs a sarcasm font.  The first person that a baby gains attachment to is the first caregiver.  If the caregiver is the one that abuses, neglects and harm that relationship, what does the baby connect to?  Sometimes no one.

In the list of best practice this one was placed number 7.  If you are listing these in order of importance this would be number one with caution written all over it.

7.       Attune to attachment issues at all times and from the first contact point

While different in presentation and levels of functioning (including at different points in their lives) complex trauma clients have sustained assaults to their ability to connect with themselves and others. Attuning to attachment issues is vital to the therapeutic alliance and to effective working within it. It also assists recognition of potential indicators of whether the client is experiencing complex or single-incident trauma. Thus, there are significant reasons for therapist sensitivity, from the first contact point, to the relational style of the client (and thereby to the possibility of underlying trauma) (Shapiro, 2010).

https://www.blueknot.org.au/Workers-Practitioners/For-Health-Professionals/Resources-for-Health-Professionals/Best-Practice-Guidelines

People would think of course you need to feel attached to someone, why the caution? For the therapist, the danger of over stepping the bounds of professionalism and creating an unhealthy co-dependency.  For the client, the intensity of finding someone they can attach to, creating a possible situation of being a bit like a barnacle on a boat.  The barnacle gets destroyed in the separation process.  The one thing that my counselor emphasized constantly was that our relationship was temporary.  He told me many times that his goal was to work himself out of job and seeing me moving forward, separated from the attachment I formed.  It is a delicate dance of trust, attachment, and appropriate boundaries.  Emotions during counseling sessions runs high….confusing what those emotions mean and how to interpret feelings and boundaries is difficult to maintain.  I worked with several counselors and none developed the strength or intensity of the first counselor.  I jokingly called him the mother I wish I had.  I still send a Mother’s Day card to him.  He also maintains very healthy boundaries.  I like that about him.  He recognized the caution that comes with this step and put in place healthy boundaries to protect himself and me.