It's called conflict of interest my good sir. Trust me, they didn't mine monero for a year then release the asics. I mined monero for over a year, the network behavior was normal until February. So its hard to believe.
Do you really believe Bitmain are angels and tell the public about their ASICs immediatly and sell them?
Dero has been secure for over a month and handing over the hashing power to asics makes the network more vulnerable because they have ALL the hashing power right now. Doesn't seem all that secure.
Dero has had extreme high hashrate attacks because of this, much higher then other coins. But in contrast to other coins it withstood the attacks. I believe the experience with these ASICs on the network will enable the Devs to create the most secure blockchain ever.