That's obviously ridiculous. Correspondingly it's very easy to poke holes in the arguments here. Let's just take the first premise, that we should (a) prevent immediate suffering, and (b) prevent future suffering. What about the very important case where I accept some suffering in the short term to reduce suffering in the long term? No indication here of where that makes sense and where it doesn't. What about a prisoner's dilemma where I may be able to prevent a lot of suffering, but only if someone else (who I have limited information about) makes the same decision I do?
These questions (What do we do about time? What do we do about society?) are just two examples of the hard questions where all the work gets done. The post doesn't explore them. In fact it seems to assume as a premise that hard questions don't really exist. If this is hedonism, the stuffy philosophers maligned by the poster have produced better arguments for hedonism than this one.
(All that said I don't think we should go too hard on the poster - at least they are trying, which is more than most people do!)