Every server right now except for high-pop servers is a disaster. You're lying if you say it isn't. You have maybe 3 ~ 4 raids of 10-mans that are good and can clear content. Then all the "rejects" form dozens upon dozens of little 10-mans that can't even clear Normal modes. The 10-man system was just a way for little cliques of friends to form a guild and never have to deal with teaching a new player how to play.
So now, you have all these new, inexperience, or just "regular" players, who are getting screwed over instead of helped. If you wanted to clear a raid in the past, you actually had to be a community and help people. Yes, part of being a 25 man is teaching your weakest player how to play. In a 10? You just cut them and replace them with someone "better", and leave anyone behind who isn't already an expert at the game.
This isn't enough. Blizzard should make all 25 gear "Thunderforged", and give 10s a tiny, tiny chance at it (10% or less). Then, all those people who are running cliquish little guilds would suddenly need to open the doors and recruit, or get run out of town by the people who learn how to form actual communities in their raids. People act like 10s are making raiding accessible... but in truth, they destroy raiding, and allow the elitists to never have to interact with the general population.
I am sure for many the 10 man system is way for cliques and friends to form guilds who never bother teaching a new player how to play. I am also sure that there are many 10 man guilds who were formed by groups of players who are not friends or cliques and who actively teach their "weak" players how to play. You are making many, many overreaching assumptions when you say that a poorly performing player is simply cut from a 10 man. This happens in 25 mans as well and to say that it happens more in 10 mans is pure opinion. Each format is a community, yes with different logistics and different pros and cons but players are players regardless and should not be treated as "inferior" if they do not choose the format you prefer.
Making all 25 gear Thunderforged could have a significant impact 10 man raiding guilds who have every right given to 25 man raiding guilds to partake in their chosen format. 10 mans are an option, 25 mans are an option, when both formats are tuned to be of equal difficulty then it really is a choice. We can argue all day long about 10 vs 25 man but it all comes down to player choice. Asking Blizzard to force players into one choice simply to benefit the raid format you feel is "superior" is selfish and your own opinion.
Players who choose the 10 man raid format over 25 mans should be not be treated any different than those who choose the 25 man raid format. We are all players who have made a choice. The only problem is when players settle instead of playing the format they really enjoy, that is when I feel Blizzard needs to step in to help bring that to the player who desires it but to do so in a way that does not demean the players who do not choose the same option.