I'll grant you understated, but Thinkpads are not better-constructed. The Macbooks are solid pieces of aluminum. I bought an X220 for my dad and it's a solid machine too, but it doesn't have the same rigidity and has more moving parts to go wrong.
That link is marketing fluff. You don't need to take a laptop to Everest to understand that moving part are prone to breakage over time or that a rigid casing will better-protect interior parts. Carbon fiber is prone to cracking while aluminum will generally just dent.
