last seen date means a single spoofed signal yields future dates forever.
Give some credit to the engineers who built these receivers and their firmware. They're extremely complex and nuanced. You can be absolutely sure that they carefully considered their options here and chose a tradeoff that made sense given the constrains they were designing for. I'm confident they anticipated them, but they just concluded that the fixes beyond using the mfgr date as a base point were worse than the disease.
It's easy to criticize from the future when we know what happened, e.g. e.g. that there was an almost 20 year delay in deployment of the modernized GPS signals and many people kept using these devices far longer than anticipated.
Give some credit to the engineers who built these receivers and their firmware. They're extremely complex and nuanced. You can be absolutely sure that they carefully considered their options here and chose a tradeoff that made sense given the constrains they were designing for. I'm confident they anticipated them, but they just concluded that the fixes beyond using the mfgr date as a base point were worse than the disease.
It's easy to criticize from the future when we know what happened, e.g. e.g. that there was an almost 20 year delay in deployment of the modernized GPS signals and many people kept using these devices far longer than anticipated.