Actual reason (beyond "it sucks", which should be enough)
Theo - t3.gg (@theo)
Antigravity is notoriously aggressive with banning people using their subscriptions outside of their tools. You can even lose your Google account along with it.
They don't offer any ACP bindings or other ways to integrate. Gemini CLI kind of did, but it was killed off in favor of the closed source garbage AGY cli.
Tbh, I'm a bit thankful. There's literally zero reasons to be using any Google model for code right now. Switch to literally anything else and you'll have a better experience :)
— https://nitter.net/theo/status/2085946505555587148#m