The author may well have found a real pattern, but it may only apply to a subset of planetary systems. Kepler is biased towards detecting large planets with short orbital periods. Perhaps tightly packed systems have similar sized planets because this is a more stable arrangement. However, more widely spaced systems - which we have far less data on - may not show this pattern.

We're learning something here but we don't really have enough information to know how remarkable our solar system is.

Humanity has only been searching for exoplanets for a very short time. That's why there are relatively few candidates farther than 1 AU out. It's somewhat like arguing that all lattes are comprised of milk only because we've only taken the first sip.