It would be a real shame if Channel 4 had to chase ratings and play things safe. Set up under the Thatcher administration, the remit to produce original content and boost home grown talent and production has been more than fulfilled and indeed exceeded according to their last annual report (
link)
Channel 4 is and should continue to be different. It's a channel that often challenges the viewer. For example, look at the Paralympics coverage and The Last Leg on disabled issues. It shouldn't need to challenge other channels and platforms.