I wholeheartedly agree. If you watch judo exams, you will notice beautiful effortless throws with uke whose sole purpose is to make the throw look outstanding. Collusion at its finest!
This is a common experience in all martial practices in my experience. If what we're trying to learn is "problem solving" while at the same time we may be also "practicing for the sake of the practice", then we should also make sure that we have a problem to solve. In my understanding that's uke's primary job description. Delivering an "attack" with the intent of disrupting the tori's posture/balance enough that they must make a recovery. Of course, this must be appropriate to the situation. The inherent danger that's possible in this attack is understood. Within proper maai tori takes control (sente) of uke with waza. Going slow, fast, soft, hard makes no difference. Of course, during this practice, the goal is to also take care of each other while we take part in the practice.
We, in my practice, should always be "testing" each other to keep it "real." This is difficult to be sure. If my uke isn't really motivated to do this all the time and recovering postural integrity, balance, etc. in order to keep the ability to continue attacking if possible, then we will be doing some sort of dance routine of a martial flavor, or what Noro sensei developed in France which he calls Ki no Michi. (pairs yoga) I have lots of respect for that, but it isn't budo.
This is, of course, my attitude about the uke/tori relationship in my ideal budo practice. Everyone has a choice about their own practice.