I just rode a century (plus 8 miles there and 8 back) Sunday on my ti fix gear. Had 4 cogs, chainwhip and Pedros Trixie tool so I could run 43 by 13, 16, 17 or 23. Not a light bike. Steel fork, sturdy tubing. Stiff as I ever would have needed in my racing days. With aluminum clinchers, I suspect weight with toolbag, pump, cages but no water bottles was ~21 pounds.
The ride? Awesome! Not just smooth rolling (on 25c Vittoria Corsa Open Pros w/ 102 psi). The bike just felt pure race and I pushed it hard. At the high point I put on the 13 tooth for the biggest decent, then stayed on it for the next 15 miles. That descent went immediately into a 180 foot climb at 8%. Hard but I felt good and the bike felt great. Yes, 5 pounds lighter would have been 2.7% faster/easier up that hill. Still, at the lowest RPM by a lot, no one passed me. (If I were racing, I'd be riding much lighter wheels. Sewups saving 125 grams per tire and tube and 150 grams plus per rim. No pump, no toolbag except the Trixie - this would be racing a road fix gear in a road fix gear race like they did 120 years ago - still need those tools to change gears.)
As has been said before, titanium makes for a completely race-able bike (and one that fares quite well through the abuse race bikes get, including crashes). They could also be made on a production floor at production speeds - but - they would have to be made on a production floor of an aerospace quality plant, perhaps with robotic welders in a separated inert atmosphere environment. Forever, off the shelf bikes at prices none of us would care for.
Ben