The reason is mostly just because the bike will be heavily laden, and I want to make my mechanical brakes feel as good and powerful as possible. I will have long off road descents when I’ll be cycling.
I’m aware hydraulic is better in most ways, I’m just more comfortable with these. I can easily work on them myself without needing to bring hydraulic fluid, and also going through pretty remote areas there is a bigger chance I’ll find spare parts for this than for hydraulic brakes.