Playing earnings

Still a noob learning about options…

1. If I want to play earnings and buy calls for next day's earnings, I assume the gain/loss potential is higher with ATM calls vs OTM calls. Correct?

2. I notice a lot of call options increasing in value near the week before the earnings date (or at least all these 0dte's and 7dte's on WSB seem ro suggest so). Why not just buy earnings calls months before the earnings date and then sell for a profit the week of?