That's a somewhat recent addition, and it does help somewhat with the Photo library problem. It sucks if you don't have a fast internet connection, though. It also sucks if there's ever a problem with the photo library, because then you don't have a backup anymore.
Maybe 240GB are enough for light usage if you store photos in the cloud. I can only say that in my experience 1TB is the bare minimum if I don't want to spend half my time copying files around.
Yeah, as I said, a somewhat recent addition. The problem with skimpy storage on base model Macs has been an issue for decades, and it has gotten worse since you can no longer upgrade with aftermarket parts.
"Optimize Storage" is a bandaid that helps make your Mac with too little storage usable. But it's not a great solution. You'll be looking at spinners a lot. It's just not a nice experience when every video you want to look at takes a few minutes to load.
Maybe 240GB are enough for light usage if you store photos in the cloud. I can only say that in my experience 1TB is the bare minimum if I don't want to spend half my time copying files around.