The first two links are of the same video. The gal had problems with it, her boyfriend didn't. You can tell she also had to keep adjusting her grip from time to time. Just like the video's title, it isn't the gun, it's the person.
The third link appears to be several months old, before the recall. The recoil spring plate is as common as any other firearm. All of my XDs and 1911s have some sort of "scratches" as he claims to have on his. His paranoia of his spring popping out and injuring him is a load of crap to say the least.
The fourth link is over a year old. He also explained why in his opinion why the light primer strikes were happening. Another case of operator error.
The fifth vid is part one of the first two links. The husband concluded that his wife can't handle guns in a .45ACP cartridge. Again, this vid is before having the gun sent in. If you read the comments, they speak for themselves.
The sixth video is a guy constantly griping his gun has lube all over it. There's nothing here, AT ALL, about testing the gun for light primer strikes.
You know, I see a pattern here. You googled XD(S) problems and just pasted away without even analyzing the results. And this is how I believe you dreamed up the "5%" assertion.
It's pretty easy to do this with any gun and stake claim of problems. Glocks are one of the most reliable firearms made. But it doesn't take two minutes to find "malfunctions" with them...only to find out people are limpwristing them or using garbage ammo such as Tula.