Trainers who actively engage with the Gym where the EX Raid Battle is taking place
and those who have invested more time into the Raid Battle feature a better chance of being invited to participate.
https://www.pokemongolive.com/en/post/novdevupdate-raids

この文前半ってEXレイド開催ジムでの通常ジム戦を指してる？それともEXレイドそのものを指してる？