Unfortunately the options that exist today are either easier to use and less hardened (Fedora) or difficult to use but more secure (QubesOS). Secureblue is the closest thing to a “middle-ground” but it isn’t very easy to use and all their hardening can only improve Linux to a limited extent. If you’re just looking for something better than Linux Mint while remaining somewhat easy to use, Fedora is definitely the way to go.
There are some quirks with atomic distros (such as Silverblue), so Fedora Workstation might be a safer bet for you. Phishing protection is more about your browser and your personal security awareness than it is about your OS. I don’t know whether there is a lot of malware that would infect Linux Mint and not Fedora but it’s still worth upgrading to Fedora IMO. I think the best defense against most malware on Linux is being selective with what software you install and where you install it from. Sticking to verified Flathub Flatpaks and your official distro repository is generally best, be extra cautious of other software sources.