The i7 2.8GHz dual core is now an i5 2.4GHz quad core.
The RAM is still 16GB.
To keep the price roughly the same the 2019 is a fixed 512GB instead of an upgradeable 1TB.
And of course, no escape or function keys but touch bar. And no SD card slot. And a keyboard replacement programme - I've replaced a few keys myself on the 2013 that wore out, I can't see me doing that one the 2019.
The 2019 hasn't arrived yet. I'm genuinely not sure whether to give her the new one and keep the six year old one for myself. That it's even in question seems ridiculous.