The problem is that there is no way to tell an SPV client that the chain they are following because it has the most proof of wo
This seems to happen frequently in Bitcoin where bad behaviour by party A can negatively effect party B, and so everybody focuses exclusively on preventing party A's bad behaviour instead of making the system more robust by removing party A's ability to negatively impact party B to solve all current and future problems.
This is a great point it's the core idea behind my diminishing faith in the majority of popular developers, they are building (developing) on top of systematic mistakes or fundamental deviations from the construct of incentives the code is needed to govern.
The problem is they are seeing their past work as progress and future fixes as necessary to overcome satoshis mistakes.
From my point of view satoshi made lots of mistakes, but where he succeeded was in aligning incentives to make a robust money, this is under threat as those incentives are sometimes considered critiqued as inefficiency.
Case in point (SPV) mining - originally employed by Ghash to improve their orphan rate this bug should have been removed to diminish their advantage, where as the developers seemed to sanction it's deployment throughout the network to balance competition.