Page count was a real concern. I wanted to introduce Rust newcomers to easy concurrency, and keep the data-storage side of things manageable (storing a big list of dynamic objects with traits gets messy fast and leads to a lot more borrow-checker fighting). Using an ECS let me dodge the latter bullet, at the expense of a bit of complexity. (I made sure Flappy didn't need an ECS)
Bevy didn't exist when I started writing, or I'd have probably used it. Legion is a great ECS, but it's heavier than I'd like - and Bevy makes a lot of things really easy.
It needs a mindset change. The thing is trying to help you. It points out issues that you didn’t think about. It’s naturally difficult to think about things you’ve never had to think about before. It also turns out that architecting software in certain ways (like ECS) makes it easier to think less about borrowing.
Bevy didn't exist when I started writing, or I'd have probably used it. Legion is a great ECS, but it's heavier than I'd like - and Bevy makes a lot of things really easy.