well for sure if this change will have a negative impact on minutes per match available for train this will affect a lot an already dying economy.
Plus teams not interested to train can train every week stamina in order to reduce the impact of the new "feature" so I see another point to not relate directly competitive of players to stamina.
Maybe could be related to a sum per week, example, if a player gets over 80 minutes on a single week, he will have a drastical drop on the field and on game shape too
1990-2022 Stalinorgel - https://www.youtube.com/watch?v=pV-Xppl6h8Et