For most of my usage 16 GB is overkill. I only occasionally have heavy enough usage to justify using more than 8 GB, and I don't use Final Cut.
However, I bought 16 GB anyways, since this will cover my occasional heavy usage, and because I find that memory usage with OSes and applications increase as time goes on, and I tend to keep my laptops a very long time. My previous laptop was a 2 GB MacBook Pro, which I eventually upgraded to 4 GB and then to 8 GB. Even though 2 GB was very usable with it when I bought it (in 2009), it's basically unusable now with 2 GB. 4 GB is tolerable with light usage, but 8 GB is definitely preferred. Unfortunately, with Apple's current laptops, they are not memory upgradable, so I just spent the extra money to get 16 GB and don't have to worry about it.
I only got 256 GB though, since for my laptops I don't need that much storage. A lot of people might want 512 GB though. (I use alot more space on my desktop, so for my iMac I have 1 TB.)
Since I already have an iMac 2012 that I’m planning on upgrading next year, I’ve been thinking that it would be better to use the iMac as an editing machine rather than buying a MacBook Pro, therefore the MacBook 12” would probably be perfect for what I do as a blogger and writer, also it would probably sit well in between my iPad Pro 12” and iMac. I’m just deciding if I should stick with the 8GB i5 Core or go 16GB and max it out a little.