A lot of tubes in the human body seem to be cases of imperfect 'design': Eustachian tube, ureters, urethra (esp. in older men), etc.
Or consider 'silent' diseases like hypertension (high blood pressure), pre-diabetes, periodontal (gum) disease. Pain system not fine-tuned.
I assume this is Jeff Lowder's Twitter account. If so, several problems with Jeff's objections.
i) It's not an undercutter, much less a defeater for Christianity, that humans develop health problems. To the contrary, Christian theology predicts for that. Mortality and illness are inevitable in a fallen world. That's not a design defect, but a punitive sanction.
ii) How is a sinus infection a mark of poor design? That's caused by something external to the organ.
iii) It's hardly a design flaw that aging organs, systems, and body parts are less efficient. Moreover, even planned obsolescence is can be a mark of good design in the sense that it was doing what it was programmed to do. And that serves a purpose.
iv) It's easy to venture armchair complaints about alleged examples of poor design, but I don't see people like Jeff producing technical schematics for better designs. In addition, what compensatory adjustments would need to be made in the body to accommodate an allegedly superior design for one particular organ or body part?
v) On the one hand, atheists complain about God-of-the-gaps arguments. On the other hand, atheists point to examples of what they deem to be suboptimal design. But isn't that a naturalism-of-the-gaps argument? They default to the bungling, groping process of naturalistic evolution. They say that's just what you'd expect if life is the result of a haphazard process. But why isn't that an ad hoc fallacy or argument from ignorance? The very thing they impute to theistic explanations?
vi) In general, would it not be disadvantageous rather than advantageous for "silent" diseases to be painful? Until the advent of modern medicine, what could be done about hypertension? How is it beneficial for the pain system to be fine-tuned to register untreatable or incurable conditions? How is it beneficial to experience pain if nothing's available for symptom relief, much less a fix for the underlying cause? Isn't that detrimental rather than beneficial?
vii) How is the fact that body parts, systems, and organs can malfunction evidence of suboptimal design? Take sports cars and luxury cars like Lexis, Mercedes, Porsche, and BMW–not to mention Rolls Royce, Ferrari, Bugatti, and Lamborghini. Sooner or later, these will break down without regular maintenance. Is that a design flaw? Are they poorly engineered?
Indeed, it wouldn't surprise me if modern high-end vehicles aren't more prone to malfunction than cars in the 1950s. Today's vehicles have so many gadgets, so many extra things to go wrong.