My understanding is Epicurus thought removal of pain was important since it didn't allow height of pleasure, BUT even if you didn't reach the height of pleasure (no pain in mind or body) you could still have predominance of pleasure over pain thanks to mental pleasures understanding limits of pain and gratitude for past goods, etc. Especially as mental pleasures are more important than physical ones
I agree with everything in that paragraph. The extra twist I would say rather than "important" I would say "the theoretical goal."
And that gets to the issue - for humans we are not going to be able to eliminate all pain if we want the most happiness possible to us. So to stress "absence of pain" as if the prime directive is to always avoid all pain is going to result in a far less happy life than if one understands that we sometimes choose pain in order to obtain greater pleasure in full.