Hopefully people still be wearing tan/brown brogues with a navy suit in 20 years time.
If you must do this (navy is timeless with a black oxford IMO), consider a dark brown rather than tan, and do keep 'em clean polished.
I wither internally on a daily basis at the sight of suits with scuffed tan brogues.
+1, don't do tan with a suit. Darker looks much better, I wouldn't go lighter than a chestnut - even that's a bit light but might be more versatile than a dark brown.
If you must do this (navy is timeless with a black oxford IMO), consider a dark brown rather than tan, and do keep 'em clean polished.
I wither internally on a daily basis at the sight of suits with scuffed tan brogues.