Everyone (who wants to make money from their app)? I own an Android and I'd still launch an iOS app first because the vast majority of mobile revenue comes from iOS, not Android. At the very most I'd use Flutter to launch on both platforms at once but I'd still prioritize the iOS side.
If you use a cross platform framework, sure, but if you only have resources for one platform (or where cross platform is not suitable for whatever reason), I'd pick launching on iOS first any day of the week.
counterpoint: you can outsource android i.e. pay a high quality dev shop to clone your iOS app and adapt it nicely for Android. I've done this several times, to great effect.
