I completely understand your point and I also believe applying stricter punishments is a terrible idea. We need encourage players to not leave, not force them to stay. Something I'd like to add to your posts, is that I believe this feature should be optional and you only would be allowed to join at certain part of the match (i.e I see no point to join when the score is already 40/40 and the game is about to end).
I also would like to point that punishment right now are not that strict. If you leave one match you'll have a 1 minute ban, the second time you'll have 2 minutes, the third 5 and so on. This seems to reset daily so you can potentially quit a match per day with getting almost no punish.
The reason why I think it's a terrible idea apply harder punishments is that there are some few games that feels very frustrating/unfair, or maps where you know the whole game will inevitably get boring (like XXXX from Reach, where all matches lasts almost ten minutes and almost always at least two people quit, glad I haven't got to play that map recently). I think if we feel this extreme discomfort in a game, it's a pain to wait the potential time that it takes to ends, so the choice of leaving is completely valid here. I rarely quit but when I do I do it for reasons which can be justified.
I also would like to point that punishment right now are not that strict. If you leave one match you'll have a 1 minute ban, the second time you'll have 2 minutes, the third 5 and so on. This seems to reset daily so you can potentially quit a match per day with getting almost no punish.
The reason why I think it's a terrible idea apply harder punishments is that there are some few games that feels very frustrating/unfair, or maps where you know the whole game will inevitably get boring (like XXXX from Reach, where all matches lasts almost ten minutes and almost always at least two people quit, glad I haven't got to play that map recently). I think if we feel this extreme discomfort in a game, it's a pain to wait the potential time that it takes to ends, so the choice of leaving is completely valid here. I rarely quit but when I do I do it for reasons which can be justified.