Everyone and their nan on reddit has been making one day cups to get easy medals, most of which sit in a backpack and never see the light of day. I'm of the attitude that medals are nice as a bit of prestige e.g. a reminder of your first season of etf2l, a celebration of supporting a charitable cause, or participating in a community wide event. I'd be surprised if anybody looks back on a competitive highlander dustbowl 1 day cup with Nostalgia, and proudly shows off the medal in game.
If the sheer quantity of medals is reducing performance and taking important time away from the devs, the decision to reduce medal additions is a no brainer, and I'd wish they'd adopted this stance sooner. I'd hope they make an exception for the next round of TOTH, and continue allowing the established community's like ETF2L to distribute medals as they have been for many seasons.