Additionally bekius sedarim in many yeshivos is a weak seder if it exists at all – I think that makes a statement in it of itself.
Ah, but what’s the cause, and what’s the effect?
It was always well known that the yeshivos were not following R’ Schach’s wishes. The only possible normal explanation would be that the roshei yeshivah saw that it would cause the bochurim to lose interest, so sacrificed the ideal way to learn, for the purpose of getting the bochurim to be interested in learning.
Anyone who thinks that R’ Schach was against iyun, though, never learned (or comprehended) his seforim. He wrote the most lomdish’e seforim in the dor. The issue is one of approach; he maintained that one must attain bekius in order to attain iyun, but he was never satisfied with just bekius.