No. I never delete accounts unless specifically requested, or if it's warranted (due to rule breaking, etc.) The worst experience for a member would be to return and find out their account no longer exists. Bad times. People get burned out and need a break. Should you have difficulties with retaining members and keeping everyone active, attempt other strategies before even remotely considering any type or pruning.
I don't delete inactive members even if they have 0 posts because they may return in the future and I don't think there is a need to deactivate their account.