@e Optimization

So, I heard that having multiple @e selectors is really bad for performance. I used to have some @e selectors in my tick function, each one targeting entities with specific tags, scores, etc, but I migrated them all over to a universal entity tick function, which runs as and at all entities and runs checks for each entity individually. Is this more efficient? How exactly does @e work for performance? Is having multiple specifically-targetted @e functions actually worse that just having one that runs on everything?