not designed for "late bloomers."
Let's face it, not all of us "peak" in our early (or even mid to late) 20's. I certainly didn't.
For example, imagine a guy who is somewhat nerdy and socially awkward in his 20's who, after years of study and struggle, ends up eventually becoming a successful doctor by his mid 30's (or, perhaps, by that age, he's making a lot of money working in the tech industry, etc.). In the meantime, he gains a lot of confidence, improves his social skills, hits the gym, etc., but is still single.
While still in his 20's, there will likely be few attractive women (LDS or otherwise) interested in this guy. But when he reaches his mid-30's, a whole world likely opens up to him if he broadens his dating pool to include non-LDS women (especially, if he gives up the alcohol part of the WOW). If, however, he limits his pool to LDS women, his options will likely be no better than when he was in his 20's (and probably worse) because the overall pool of attractive (and not crazy) single LDS women is so much smaller (and this situation is even worse for single LDS women because the pool of attractive (and not crazy) single LDS men is smaller still).
Of course, there are many positives to LDS dating that we tend to take for granted. For example, from a purely practical perspective, lower likelihood of contacting a STD or having substance abuse issues ruin a relationship. But it's definitely set up to favor early bloomers over late ones.