From what I know it's considered "better" because it's one of the first to use things like shadowsocks.
Usually ISP can detect you are using a VPN, some countries/isp actively block it.
With obfuscation it looks like normal trafic thus, harder to block or to detect you are using VPN at all.
"Mullvad's Shadowsocks integration is designed to help users bypass internet censorship and restrictive firewalls by routing traffic through obfuscated bridge servers."