I will note that it would be technologically possible to braze a Ti mainframe in house.
"The best defense against copying is innovation.” Will Butler-Adams
Brazing Titanium is extremely tough, to weld it needs to be super clean in the shop, to braze apparently it needs to be even cleaner and it might be best to do it in a vacuum rather than the normal back purge of Argon gas (or other inert gas) However I am not a brazing expert I just had done some research after wanting a filet brazed ti frame a while back and realized that was not really feasible. I am excited for whatever they bring as a full Ti Brompton would be cool.
I do like the quote though!