Let's see who the new people are before we pass judgement here. There's no reason Trump needs to stay with Obama's people here.
Trump's track record has been not to replace "Obama's people" with anyone and to leave positions vacation. Pruitt wants to replace scientists with employees of the industries being regulated.
I predict this will hurt the departments in the long term because the review and comments will still take place, but outside the departments and after they've stuck their neck out for bad policy. Trump and his people will still do a lot of damage, but they can't completely silence the opposition.