Titanium can be a VERY difficult metal to machine. Gun makers seem to pursue the MOM- Metal of the Month. How many of us never HEARD of Scandium before S&W marked that on a frame? You should be able to shoot .357 in any gun marked .357- and a .38 Special +P is FAR less energy than a .357. Of course, thre is no such critter as a .357+P.
Now, having said that- all other things being equal, the lighter gun is going to recoil more. (Ow). Some guns will experience accelerated wear when shot a LOT with full bore magnum loads (S&W Mdl 65s come to mind). It is not going to go KABLOOIE- it is going to get loose. However, titanium alloys are tougher than hell, and should withstand the punishment as well or better than stainless.
Hopefully, some of our pistolsmiths that have seen some of those after lenghty use will chime in with some more objective info.
What we have here is... failure- to communicate.