Changing out brake fluid can be a real benefit.
I agree. because, of course, brake fluid is hygroscopic, the water it attracts can quickly lower its boiling point.
I recently replaced all the flexible brake hoses on my 4/4 with Goodridge s/s braided items so it gave me a good chance to drain and clean the system thoroughly.
I tend to do it every one or at most two years but I have seen a number of vehicle maintenance manuals which recommend annual changes as essential
Cheers,
G
