The carbon footprint of regular business jets is increasingly criticized, so flying around in something that’s bound to emit even more for a speed advantage is not going to endear you to the public. While that certainly won’t deter all possible buyers it is bound to deter an increasing percentage.
The increased market presence of GTF and the possible re-emergence of open rotor fans (or maybe even a new turboprop) might lead to an overall slowdown for environment’s sake. For many applications it doesn’t really matter whether you cruise at M0.6 like a Dash 8-400 or at M0.75-.80 because the difference in overall travel time is minuscule but the fuel savings are huge.