And neither of those will happen at games events with an open letter.
The goal for something like the Gaza conflict is to change public opinion. You do that by being very visible and getting on the news consistently enough for people to decide to look more into it. The protest at government buildings isn’t intended to change policy makers’ minds directly, it’s to get media attention in a place that has symbolic significance to viewers, and that change in viewer opinion is what policy makers care about.
At the same time, meet with reps in their offices to discuss mutually beneficial options. For something like Gaza, that means getting humanitarian aid to Gaza, which doesn’t require the politician to flip on their support for Israel, but still shows a shift toward supporting Palestinians. As public opinion starts to change, push for ceasefires to establish humanitarian aid corridors, peace talks, etc. None or that requires the rep to abandon support for Israel, you’re just pushing for peace.
Imo, that’s how you get change. Open letters that most people will ignore do nothing but rile up people who have already formed an opinion on one side or the other.