A similar question to that one, but this one is concerning the suborbital SpaceShipOne spaceplane. Could it be reactivated for space tourism or other purposes? I remember in 2011 some sources stated that the SpaceShipOne also was to be used for tourism flights, along with the SpaceShipTwo or something like that.
There is absolutely no reason to ever even conceive of flying it again. It was retired because it successfully did the sole task it was designed to do.
SpaceShipOne was unsafe1, barely met its requirements2 (which was certainly good enough) and was designed specifically and solely to win the prize.
The tiny crew compartment meant that there was zero incentive to certify it for passengers; it would certainly have not been economic for tourist flights.
I wouldn't call it a prototype since it was designed to meet certain requirements, met them, and was retired before it killed anybody.
1 "SpaceShipOne had lost control. It spiraled up, making twenty-nine rotations."
2 "To solve the problem that SpaceShipOne barely reached space even when much lighter than it would have been for an Ansari X Prize attempt..."
Source: Burt Rutan's Race to Space, Dan Linehan, 2011
SpaceShipOne was retired so quickly because it was a prototype.
One of the key lessons-learned over the last seventy-plus years was that the waterfall model does not work when applied to creating something that is substantially new.
Another of the key lessons-learned in the same timeframe was that prototyping is a very good way of what I call "debugging the blank sheet of paper", as in "this blank sheet of paper is supposed to contain the design of a spacecraft. Fix it!"
A final key lesson-learned is that prototypes should be tossed. The purpose of building a prototype is to start solving the blank sheet of paper problem. In doing so, many of the rules regarding what constitutes good engineering judgment oftentimes were ignored.
Not all organizations have learned this lesson. Scaled Composites apparently has. They built a functional prototype, gained some knowledge from that endeavor, and then they threw it out. They then built another prototype and they threw that out, too.
There is nothing wrong with throwing out a prototype. Nothing at all. On the other hand, there are many things wrong with not throwing out a prototype. Throwing out a prototype is not a sunk cost. The prototype did its job, and far more cost effectively than a waterfall model based approach possibly could.