I'm pretty sure the amount of users that actually like this opt-out behaviour (everything gets suspended by default) is a minority. Instead what they choose to

I'm pretty sure the amount of users that actually like this opt-out behaviour (everything gets suspended by default) is a minority. Instead what they choose to do is not worry about memory until it you actually run out of it. I don't mind my applications taking up 90% of my memory if that keeps everything fast and I don't have to worry about keeping track and thinking about what I actually want to suspend and what I dont't. If you really do mind, just run any of the plugins that implements your exact required behaviour (like the great suspender).