I have just recently found out about how guardians were disabled from spawning. I believe guardians should be enabled as they don't cause lag as much as obvious things like elytras, minecarts and boats. However the blame on server lag was put on guardians. Before guardians were disabled and elytras were re-enabled I experienced lag and rerolling every 1/2 an hour or so. Now with elytras enabled and guardians disabled the server rerolls every minute. This makes stuff like mining impossible. Guardian farms have been a thing for awhile and just now they are disabled "due to lag" while an item proving to lag the server has just been re-enabled. I believe guardians should to be re-enabled as many people have guardian farms and poured a lot of time and money in to them and it was all replaced for elytras and minecarts and boats.