Why do I trust it? Because it continues to work, can it fail? Sure, but there is little incentive for those in power to mess around as it would jeopardize the system.
> The money that never exists in any form other than on some computers
I'm not going to get into how money works - but your statement could be said about crypto, it only exists on some computer right? Just because it never existed before doesn't mean it won't have utility.
I think the legal system is the real place to fix things - there are certain mechanisms which influence how wealth works its way through the system. At the moment its misbalanced. It has little to do with the USD (well I benefit from USD, perhaps little countries elsewhere have a gripe with it).