Aren't we talking about, on average per month, one class getting like one fairly important update (like the sneak attack going 1/turn) and then several of their powers getting updates (so that maybe a high-level character has one or two of those powers)? Since a given game table only has 5 or 6 classes represented, how is that snowballing as big as you are talking about? You could go your whole life without bumping into many of these changes.
It's not just character powers (though those are the most obvious, and the most quickly noticed). Sometimes it's rules or other bits that, like you said, we might never have run across except for a specific scenario that induced us to look up the rules and find contradictions between the rulebook and character sheet.
Stealth rules are a good example of that one.
Sounds to me like come and get it snagged you attention, but how often is this really turning up in any game?
Come And Get It, Winged Horde and Cannith Goggles were the trifecta that really drove it home recently. They were by no means the first time or only times its happened to us, though.
Confirmation bias mixed with hyperbole is not a good way to judge an issue.
Yup, I know... That knowledge doesn't make the visceral perception of the problem any less frustrating, though.
Anyway, how often are you even leveling up? Not that I object to fast leveling but still, there aren't that many updates, and there aren't that many levels.
We try to meet weekly for our game, and depending on how faithful we are to that schedule, we usually level up once every month to two months.
Though I have no hard numbers, it seems as if we've been running into unexpected rules changes about once every week to two weeks on average.
Often, these are small changes that have no real impact on the game, but still disrupt play, because we have to stop and reorient ourselves with the change. Sometimes, it's a change we've run into before, but because of the obscurity of the rule and it's subsequent change, every time we run across it we have to stop the game and consult multiple sources to sort things out.
The sort of change that you're suggesting happens maybe once every level up, but tends to be a bigger disruption, because it sometimes involves the player wanting to swap out the power for something else.