That depends, if you received restriction under the provisions of an Article 15 then yes it is punishment.
However, if your pass privileges were revoked by the Commander then no, it is not punishment. This is known as revocation of privileges. You can have your pass privileges revoked and your movements can be defined by the Commander. In this case it is not called restriction because restriction is a punishment, revocation of a privilege by a Commander is not considered restriction.
There are a number of privileges than can be revoked by Commanders who want to get a Soldier’s attention. This is a technique that is often used in conjunction with Corrective Training.
Read The Mentor: Everything you need to know about leadership and counseling for more information about Counseling, Leadership, Corrective Training, and Separations in the Army.