To be honest, I wondered ..... if the attraction of ti bike is strongest when they buy it but it faded over time and folks returned to carbon or steel, as if the ti desire was less about ride quality than they’d thought.
Most people who buy Ti don't sell the bike, so whether or not it was exactly what they had always dreamed of, .... and if they bought more bikes usually they seem to have been bikes for other purposes. I have never heard a story of a person who got a Ti bike expecting some magic-carpet-ride and then went to steel or CF to find it because Ti did not deliver.
I'd bet that if you really wanted a plush ride on an unsuspended road bike, going custom and asking the builder to aim for compliance would be the route. Slimmer chain- and seat stays, more curve in the fork, and there you are ... and the main triangle can be as rigid as you like ... I'd guess.