

You should always verify signature and hash for any software you are installing but also keep in mind that if someone was really trying to send you a malicious download then there’s good chance that they will also deliver you a malicious signing key and hash. And there is really no good solution. If it is critical you can try to get signings keys from different places and with different IPs and maybe even different devices but pick and choose how long do you want to go down this rabbit hole.
That’s a bad advice you don’t know how they are updating it. If it is added in the repo then package manager will check the signing key but if it is an in app update then that may not be verifying the new package and if someone is doing MITM they can switch it up