I experienced this in arena back in the day when crystals were there. I am so lucky my fleet shard is totally easy going and reasonable. Living in Japan, my payout definitely wasn't affecting anyone in the arena, but they wouldn't allow me to climb beyond top 20. One guy in particular must have been unemployed, cause as soon as my battle was done he was attacking me. I sympathize with the OP. My experience with the shard mafia almost made me quit.
I do wonder if rewards based on your highest rank within a 24 hour period would help alleviate this sort of behavior.