I have never really had a problem with IO raider as it sorta replaced the other measuring sticks that have fallen out of favor since I level addon in WOTLK. What does bother me is how some people go by it as the golden standard of identifying how progressed people are in either raids or mythic dungeons. Had a high rating PVP warrior with a very high IO rating as well join our piddly +12 dungeon. Let us just say his performance was the lowest of the group and out of the blue he admitted he was not use to his newly boosted alt that got carried by his friends.
He claimed that his character was just not properly set up with his keyboard/mouse layout afterward when no one was even accusing him outside of a few whispers of confusion. We still managed the key but considering his constant dying and my anecdotal evidence it would leave one to believe that this constant pushing of pay for gear that RMT and legit boosters are heavily skewing the numbers. It's not very well talked about and another issue I am starting to see no one brings up are guilds also paying for people to be boosted. Maybe IO Raider no longer has a place in wow unless Blizzard somehow allows us to track with who is grouped with these people who are being boosted to see where the actual experience of content lies. If they start allowing us to track with the people who group with boosted people it could give other players a complete picture and maybe give us tools to combat who is circumventing gameplay mechanics for pay to win scenario's and expecting other groups to automatically accept them based on false information?