Titanium is expensive.
If we are talking mass production, the prices should drop.
The US is metals poor and relies on Russia and China for much of its supply of 17 key metals. We import ~80% of our titanium, most of it from Russia. We have zero in the national stockpile; ~35,000 metric tons sold off between 1998-2005 to pay for the WWII memorial (thanks Clinton, GWB, Congress). The titanium buy weight for one F-35 is 30,000 lbs/15 tons.
The amount of titanium to produce silencers is probably trivial compared to the needs of civilian & military aircraft industries. It does highlight the need for us to have more favorable suppliers for all our key metals, including from US sources.