Let's forget what we have already invested mentally in this idea. The influence of local events on trip planning is often exaggerated and not always "drastic," because it heavily depends on the type of traveler and their specific objectives.
For a business traveler with a strict schedule, a local festival can even be an opportunity for networking rather than an obstacle to avoid, especially if they have already secured their accommodation.
For example, during the Africa Cup of Nations here in Ivory Coast, Abidjan became more expensive, but for someone coming for a conference or a major meeting already planned, the impact on their main goal was minimal, if not nonexistent.
The essential question is whether we would reevaluate this impact in the same way if we hadn't already paid so much attention to the idea that it is always a blocking factor.