Of course one would not burn pB in a tokamak. So, that number is not relevant, although it is always trotted out to justify not diverting money from tokamak.
Practical pB designs rely on colliding beams as in the LHC, or other plasma-dynamic schemes that engage the materials in their own confinement.
Colliding beam schemes for p-11B will not work, as was shown by Rider and Nevins decades ago. This didn't stop TAE from selling such a scheme to investors, even though they were told it didn't work.
Practical pB designs rely on colliding beams as in the LHC, or other plasma-dynamic schemes that engage the materials in their own confinement.