Yeah, in general, when something happens that make someone's idol look bad, they tend to shift the blame onto someone else (including other idols they're not fans of) or they try to find an excuse for their idol.
Examples:
(they might not exactly fit, but it's just something I want to rant about without making a thread about it):
Youtube just recommended me a video of side-by-side videos of professional dancers and idols dancing the same choreo. Many comments were saying the professionals danced it better, and then idol fans start defending their idols by saying that they weren't even trying their best. But then, I found a video that only had the idols dancing the choreo and no comments said anything like "wow their dancing is so good despite them not trying their best".
Also in the video mentioned above and in a SWF-related rant on this subreddit or a similar one, idol fans not happy with their idols dancing being compared to professional dancers use the "different professions" card to say that they shouldn't be compared to each other. As in, idols can sing + dance, so of course they can't dance as well as professional dancers. But that's like assuming professional dancers can't sing and the only reason they're dancers and not idols is because they can't sing. Anyways...I've came across quite a few pro dancers that can sing and some are probably better than the average idol at singing.