Verizon and AT&T confirm they aren't blocking Apple's Private Relay VPN-like feature -

Both Verizon and AT&T confirmed to The Verge that they are not blocking Apple's iCloud Private Relay feature, which works almost like a VPN service. Verizon spokesperson George L. Koroneos stated that Apple's Private Relay feature works on cellular and Fios internet connections. Seth Bloom, an AT&T spokesperson, also stated that AT&T's policy is against blocking Apple's Private Relay feature.The Verizon and AT&T statements came in response to public allegations that T-Mobile was blocking Apple's Private Relay feature. As we reported, numerous T-Mobile customers have complained that they couldn't use Apple's Private Relay feature because T-Mobile was blocking the service.

According to T-Mobile, only customers using a plan with activated content filtering (e.g. parent controls) aren’t able to use iCloud Private Relay. The reason for that is that Apple's Private Relay won't allow these content filtering services to work as intended.

Apple's iCloud Private Relay is a VPN-like service that, when enabled, hides your private information from third parties. These third parties also include Apple and your carrier. iCloud Private Relay also makes sure that no one can identify you without permission or track the sites you visit. Apple's Private Relay is currently in beta in iOS 15 and iPadOS 15. In order to use it, you must have an active iCloud Plus subscription plan.