I think it boils down to your threat model and who you trust eh? I trust Mullvad way more than I trust Comcast. The problem with not trusting anyone, including companies like Mullvad is that you've soon backed yourself into this weird corner where you have to become a C developer so you can review the code of your Linux distro and building your own routers with pfsense. Oh, don't forget to review that code too. And how can you trust that your computer firmware doesn't have some built in back doors or tracking features enabled? Before long, you're living in a cabin without electricity, sending people letters with pen and paper... which sounds kind of nice.
Oh, here is a better post about VPNs: You want Tor Browser ... not a VPN.