Is decentralized VPN real?

I'm curious, could you elaborate on the authenticity of decentralized VPNs? With the growing concern over privacy and security in the digital age, decentralized VPNs have gained traction as a potential solution. However, are they truly decentralized, or is it just a marketing gimmick? What are the benefits and drawbacks of using a decentralized VPN compared to traditional VPNs? Furthermore, how can users ensure they're selecting a reputable and secure decentralized VPN service?