Exactly how would you implement such sanctions fairly? How do you define a player who is deliberately stalling? How do you tell the difference between a game that just doesn't have enough time to finish before the end of the season? Or what about a situation where a player actually has some kind of life events going on that mean they're around less frequently than is needed to finish the game? Without having a human examine each Arena game that doesn't complete in time and make some kind of subjective decision (because BGA doesn't have the manpower for that, and neither would it solve much, as people would still complain even if it happened), what do you suggest to manage this?
BGA already prevent new turn-based games from starting within 5 days of Arena end to try and mitigate this. It's an imperfect process because it's one rule for hundreds of games. I've easily finished turn-based Arena games in 24 hours or less (depending on the game and availability of players), but yes, others can take weeks, even without anyone going over time. They've obviously chosen 5 days as a reasonable balance for that, and then it's left up to players. The framework then makes the best decision they feel it can based on available information and without requiring human intervention. What's your actual suggestion to do it differently?