What we can agree on is that the impact of local events on trip planning is real, but the term “drastically” often overstates their decisive role, as other factors can push them to the background.
There is a common ground to be found between the importance of events and constraint realities.
For example, during the Grand Magal of Touba, a major event in Senegal, transportation and accommodation are heavily impacted, which is an undeniable truth.
However, for someone who must absolutely attend a family wedding at that time, the event becomes a constraint to manage, not a reason to change destination.
The true impact really depends on individual priorities and trip objectives.