The USPS is still important. For example, no private carrier has a Constitutional mandate to serve all Americans. They are essential for rural communities: for example, if you need medication but there's no pharmacy nearby, the USPS will deliver it to your house even if UPS and FedEx won't.
Also, the USPS kicks everyone's ass in time and cost when it comes to delivering small packages. For a 12-oz package from NY to SF, USPS delivers in 3 days for about $2 while FedEx and UPS start at ~5 days and $10.
I've also never had USPS hold a package because it got to me too quickly, and I've absolutely had commercial carriers do that to maintain artificial separation between service tiers.
Don't conflate the Universal Service Obligation with door-to-door delivery; my dad has to go to the post office to pick up his mail. Of course, he lives on the Big Island of Hawai'i so it's a small price to pay.
Arguably a bargain, but considerably more than $2.
Separately, I disagree with your implication that the USPS has an obligation to deliver to your house. Do you know what the exact law or statute is?
I'm familiar with several places where this is not true, where Fedex and UPS will deliver to the door but USPS will not. Some of these are very rural ranches in the Southwest, but others are just small towns that do not offer delivery services and instead hold all mail at the post office.
> For a 12-oz package from NY to SF, USPS delivers in 3 days for about $2 while FedEx and UPS start at ~5 days and $10.
The price comparisons aren't fair. UPS and FedEx either turn a profit or go out of business. You can see this when you compare the two groups on tracking, customer service, innovation in logistics, etc. If a business depends on paying customers who have choice, despite the disadvantages they have when compared to the USPS, they find ways to improve their services and cut costs.
Meanwhile, the USPS can tap on the government's shoulder and artificially remain in business.
Also, the USPS kicks everyone's ass in time and cost when it comes to delivering small packages. For a 12-oz package from NY to SF, USPS delivers in 3 days for about $2 while FedEx and UPS start at ~5 days and $10.