That it's relative share in GDP is down during that time means that other sectors were growing even faster (think Google, Netflix and so on, so services instead of things). That the service sector gains in relative importance is actually a sign of an advanced economy, every modern economy looks like that, not just the US.
Here, US manufacturing output is up 50% since 2010: https://www.macrotrends.net/global-metrics/countries/USA/uni...
That it's relative share in GDP is down during that time means that other sectors were growing even faster (think Google, Netflix and so on, so services instead of things). That the service sector gains in relative importance is actually a sign of an advanced economy, every modern economy looks like that, not just the US.