For physiological level replacement, not a lot. But also, you don't get a whole lot of additional benefit for going over the lower end of the reference range, and people usually don't fall below that.
Isnt the issue that it happens quite a lot more since test levels on average dropped a ton? (in part due to various lifestyle choices which should be focused on first but arguably also due to various polutants)
I strongly suspect that most of the issues correlated with low testosterone are co-symptoms rather than caused by it. From my research, it doesn't seem like going much above the lower end of the T range carries much additional benefit, other than muscle mass, and testosterone replacement in people with merely low testosterone doesn't do as much good as people think it does.