I think these youtubers started off with decent intentions to allow people who couldn't see games on the telly or wanted to avoid certain commentators, mainly abroad, but they all get sucked into that race to the bottom and need to do something that attracts "viewers". They end up as performing monkeys, only without the brains.
What I really object to is having some of these turning up as "pundits" on channels like Sky or Talksport who operate under broadcasting rules, when they themselves have made a living outside of those controls and have said any old shite they wanted. I guess they invite wankers on like Brent to make Melissa Reddy sound intelligent.