Loot-Sink and Player Activity
I think it boils down to two factors: The Loot-Sink and player activity. The Loot-Sink really isn't a bad thing, as it keeps loot from becoming too common, upgrades from becoming too easy to obtain; and slows down the inevitable horde of maxed TH10s with nothing left to do but curb-stomp your base into oblivion for trophies. (By Loot-Sink I mean mainly walls, but really everything since SuperCell makes sure that everything you do as you progress costs more and more loot...)
*TLDR: The "Magic loot wells" that SuperCell has blessed us with are drying up because too many people are looting them, and are looting them too often. Players then dump the loot out of the game, and can dump all but the pennies and foam in the bottoms of their stores because the threshold for amount of loot you can waste on walls/etc is so low.
*So the reason these two factors have such a huge impact on the game is because SuperCell limits how fast loot can get into the game in the first place. Collectors are only going to produce so much an hour (unless you pay to gem them of course), and I think there is a limit on how many abandoned bases can get into the game (per hour/some obviously hidden factor for a reason). What ends up happening then, is that because of how active players are, they are always going to be keeping their collectors low, raiding all the inactives, and then dumping that right on out of the game. You then see them after they've logged out, and with no loot. This is exponentially worse due to the fact that... Idk... people hear that this game is fun and then want to start playing. So you have this huge spike of new players just this year (SuperCell went from 100m to 900m annual income) that want to play most of the day because it's fun. So all day they can constantly dump loot out of the game due to fast/fast-ish upgrades, and new walls every TH level. They also contribute nothing to the higher end loot due to godawful loot penalties and the fact that their loot-sink threshold is so low. Seriously, you can get down to 0 in your stores w/o even trying. Plus half of them don't even bother leveling their collectors because it takes days to do so; or they could just raid mine today, yours tomorrow, and some AFK's the day after that.
How do you fix this you say? Well you could do it a few ways... boosting loot from wars and offering 1-gem collector boosts is a temporary fix, sure... But war bonuses are barely positive on Dark and regular elixer anyways, and gemming every player's collectors permanently will leave the same problem, just slightly more loot and less complaints. League bonuses are a joke, and I think they were really only put into place to encourage caring about trophies (which are also a joke). Plus increasing them probably won't happen since they would be HIGHLY exploitable if the community could ever be that organized (yeah right).
Edit: War loot bonuses are only obtained once every 3 days, and that's IF you win... Yet another way that loot flow is restricted into the game.
We could also just set all our collectors and stores out to the side so that all the new people can catch up to us. When we log in a few months/half a year from now they will have their own maxed collectors and 1m wall upgrades/4m tower upgrades to save up for, and we can finally all start seeing loot again.
I think what SuperCell really needs to do is create a way for loot to get into the game that is affected by player activity. Preferably that is fun or unavoidable so that people actually participate, does not benefit the player directly so that they don't just stop participating once they've got what they need, and is scalar to TH level so that it benefits all levels fairly.
