Could high density abrasion-resistant ceramic turbine blades allow for the use of borane fuels?
Borane fuels are not practical for a multiple-use aircraft, primarily because there are no naturally occurring sources they could be easily derived from. This rules them out commercially, and gives a military disadvantage of being unable to utilize local supply chains. 

Note that the XB-70's borane fuel was to be carried in addition to kerosene, for one high-speed dash. Even though capable of multiple flights, the military purpose of nuclear bombers would have been fulfilled in a single mission. 

Modern turbines are built with tighter tolerances than those of the 1960s. This would make a fuel that deposits solid particles, as pentaborane does, more of a problem, not less. 

These considerations essentially limit pentaborane to simpler and single-use engines that can tolerate this, such as rockets. 

However, the fact that no space missions have used pentaborane, even when it cost nothing and had to be destroyed, suggests that its toxicity and near-impossibility of safe handling on industrial scale outweigh its advantages even in such applications.

To quote the paper, 


  When reading about pentaborane, a TLV of .005 ppm and indications that it is pyrophoric over a wide range of oxygen concentrations meant this was toxic material prone to ignite very easily. What is difficult to comprehend from these numbers and quantitative data is that pentaborane is as toxic as some of our Nation’s nerve warfare agents and will spontaneously burst into persistent flame in nearly oxygen deficient atmospheres. 


Spacecraft are no strangers to exotic and highly toxic fuels, such as hydrazine. However, pentaborane turned out to be on another level of difficult. It's also not as high-performing as hydrogen or the record holder Li-F2-H2 tripropellant, also not used for similar reasons.