Yes, thanks for clarifying.Chino said fixed wing. A fixed wing aircraft is not necessarily a fast mover. I think Chino is concerned about survivability in his post.
IMHO, helicopters are much more vulnerable to AA missile coverage than fast movers. Dzirhan will correct me if I am wrong.
They are definitely more vulnerable to ground fire. Everything comes with a price.
Furthermore you need fixed-wing air-superiority otherwise these attack helos will also be vulnerable to enemy fighters well before they reach their destination. Which is why a fighter-bomber is more cost-effective.