I would disagree with that, personally. He was certainly the best candidate.
Conservatives were up against big bucks from GOPe and an extensive political network and GOTV. Brooks did well considering.
Mo Brooks is a recovering Never Trumper. Looks like a garden variety climbing careerist, IMO. No loss.
http://www.al.com/news/index.ssf/2016/02/why_will_mo_brooks_never_endor.html