That's an interesting twist to p-11B economics. We haven't discussed reactor component lifetimes much here yet. Maybe we should dig out some of those studies. It's conceivable that even thermal p-B11 plants are better than D-D/T with that taken into consideration, even with the giant hit in reactivity, esp if POPS is viable (obviously there's a point of diminishing returns from power density from D-D/T due to the first wall issue, after which you might exchange power for aneutronicity and come out ahead even without direct conversion).Decrease the neutron rate by a factor of 1000, as in a thermal p-¹¹B reactor, and a core that would have lasted six months is suddenly good for five centuries, at least as far as neutron damage is concerned (and assuming all neutrons are equal, which they aren't - p-¹¹B neutrons are lower-energy than D-T or D-D neutrons).
Decrease the neutron rate by a factor of 1e8, as predicted for a p-¹¹B Polywell, and a comparable core is now good (in a neutron-damage sense) for fifty million years...
For D-D/T, if there are no interconnects (as we expect from the WB-8 design) then the outer layer of the Magrid components are presumably the main concern (and they have to carry the Magrid charge, which may complicate things a bit).
I think at one point Simon had a notion to add boron in a layer around the coolant or to the coolant itself, which would help internal components.