One thing that I have heard/read in the past is that “raiding success” also influences the algorithm, favoring less successful players. E.g. if you lose a few raids, you will receive better rewards for easier opponents in future.
On the other hand, of course, if you always win your raids, your rewards decrease and match making gives you harder opponents.
This approach might look convincing at first, with the assumption this adjustments will only balance initially unsuitable match making values and it will lead to fair and equal matching conditions where everyone finally gets equally strong opponents to oneself, where he can be successful most of the time. Though, in fact that means the system is punishing skill and rewarding failure - if you have the same stats as someone else, but are a better raider, you get punished with harder opponents and less rewards, the other one gets rewarded with easier opponents and better rewards.
Also, that approach obviously allows for exploits - first just willingly lose a few times with like 0-5% (maybe even dumping your trophies on a particular other player), then you can easily strip trophies from players that you would usually have a hard time getting any trophies from.
And while I never liked intentional trophy dumping, pushing, stripping, dropping etc., I actually dropped trophies (onto random match maker opponents) once, while visiting another alliance without boosts, where keeping my usual trophy level wouldn’t have been possible anyway, and also the usual all-boosted match maker bases would have been impossible to win anyways. So I basically used the time for completing the “summon 5k paladins” achievement and kept scoring very low percentages on every raid with paladin-mass-spawn, to see how low I could get just by using the oh-so-awesome paladins.
Well, about 2 days later I had dropped down by like 1.5-2k trophies, and found myself getting noobishly-easy match making opponents all the time. All of those were about 500 trophies lower than my already-lowered trophy count (in contrast to regularly, where the match maker usually offers you about ± 200 trophies around your own trophy lvl), barely or not at all boosted, and really easily winnable. To be clear, I could beat any of those with just my king and spells (without troops), or even with (unboosted!) troops and without any spells.
Nonetheless, each and every of those REALLY way-too-weak-for-me bases offered me between 30 and 50 trophies, and even with a like 10% raid I couldn’t really lose any more trophies.
At the same time, anyone weak enough to get me in match making did either skip me (wise decision) or horribly failed on my completely-unboosted (and full of useless unboosted bomb towers!) base (waaay easier than usual boosted base), giving me many trophies despite my base was still way stronger than probably anything they would have ever met before.
Needless to say, I was able to easily get back up to my original trophy count, just by getting attacked from poor low/medium lvl players (sorry for anyone that attacked me there), and by getting +40-50 trophies for every single noobishly-easy match maker attack. And even without match maker (from leaderboard pick), I could easily get like +20 trophies from players that were like 0.5-1k trophies below my usual trophy level.
Anyway, those few days gave me a pretty interesting insight into the trophy calculation system, I’d say… forget player strength, welcome trophy lvl differences and recent raiding success.
Summing up… stronger, higher-lvl and/or higher-trophy players gaining trophies from you despite they don’t get any good result while raiding your base is definitely no particular bug, and nothing really spectacular.
It is nothing else than the logical consequence of the trophy distribution algorithm being based on trophy differences and raiding success rather than actual base strength.
Whether that algorithm per se might be questionable is of course another issue, but individual outcomes are most likely only a result of the algorithm even if they don’t seem plausible at first.