It really depends on what one is wanting. A VPN provides an encrypted tunnel, so just end to end encryption, a VPN is redundant. However, VPNs tend to be for privacy and having a certain IP range than security. For example, one can't really choose multiple ISPs. At most, they might have Comcast, or AT&T. However, one can choose VPN services, so even though one ISP logs everything and sells it, having a VPN that doesn't do that, provides a lot of privacy.
Then, there is access to remote resources. Having a VPN that connects you to a known stated address pool makes it easier to only allow a range for a remote connection. For example, someone having a linode machine can just limit incoming SSH to the IP range of a VPN service, which, when combined with key only authentication, or something two factor, can limit the attack surface from remote greatly. Especially if the VPN requires 2FA.
Even if the ISP is trusted, using a VPN on a device can be good, because any link in the chain on the LAN can be eavesdropping and logging traffic. By using a VPN, all those devices, be it a core router, edge router, gateway, AP, firewall, now just see traffic going from the device to the VPN server.
The VPN ads don't help. VPNs are not a magical security silver bullet. Stuff like having firewalls on connections and such are nice, but they are not something to make people go out and purchase a subscription. However, for people that want an increased privacy level, VPNs are definitely helpful.
Of course, it goes without saying... choose your VPN provider wisely. When Sara Palin had her email hacked, it was reportedly the VPN provider who delivered the goods on the user who did it.