What a crock! This is the corollary of the "you're not a true submissive if..."-garbage ... apparently you're not a true dominant if you give a shit.

<if that wasn't judgmental enough, feel free to insert an expletive or your choice somewhere in there>

So what was his suggestion? Just toss the crop down and walk away? Maybe that works for him and who he plays with, but if nurturing aftercare works for you, stick with it.

When my kitten and I finish a good scene she sometimes can't walk. I do the cleanup, get her water or anything else she needs, and if she needs to move somewhere I'll by god carry her if I have to. That isn't "stepping out of role", that's caring for and nurturing what I prize and treasure beyond anything.