I have a 2012 i7 2.6ghz quad mini that I use exclusively for video and audio editing (although I use Final Cut Pro and Logic Pro). It works very well for my needs, which is primarily 1080p30 and a lot of legacy SD video. But I wouldn't buy one today, especially if I was sending it away to college with my daughter. I agree, it is getting too old. The base model 2018 has the same geekbench rating as the 2012 quad and also has a better selection of ports, faster wifi and other improvements.
I'm keeping my quad for awhile since it works for me and I don't want to spend the money on a new one. But that is not the same as setting up a new one and then sending it away. Two years ago, I gave my 2012 base mini (upgraded with a SSD and 16gb) to my daughter's family. Several months later they started having some odd problems that were difficult for me to diagnose over the phone, and they ended up having to restore from time machine several times over the coming months. They finally gave up on it, and this Christmas I gave them a new MacBook Air since they decided a laptop would be more useful.
Is there some reason why you are only considering a Mini? I'd think a laptop would be a better choice for a college student.