I've seen this countless times both in both Tech and the NGO world - some roadmap is running pretty good, managers then hire a bunch of "cool looking people that come in with a big old white board to make a cool workshop" then follow the process for a short amount of time, giving extremely shitty advice because they haven't been involved in the process at all and are going to leave soon without delivering anything.
And the fact that they are often paid a higher wage than the people who have to actually clean up after their crap advice is straight up offensive. And it seems everyone i know have this impression in both softer and harder sectors.
I've only met a few "lone wolf" consultants in Tech that were nice, people often with a huge passion and knowledge for something concrete and not "passion for leadership / some bullshit organisational fad".