No, as of January 1, 2025, the agreement between UPS and the US Post Office (USPS) expired, so all UPS SurePost® shipments are moved by UPS and NOT by the US Post Office (USPS). You must either drop off your UPS SurePost® shipment at a UPS location, or you can schedule a pickup for it.
See also: “How do I ship to or from a UPS location?”