Chromium Browsers are more secure if you use the native package.
This conclusion is relative for everyone as we all have different security needs. Plus there's no easier, better supported way to sandbox Chrome on Linux other than using Flatpak's permission model.
It's also ironic for you to be speaking about security when you are installing/updating your browser using random curl bash scripts.
Whatever you do, make sure you setup firewall properly and enable automatic updates for your software. People say this last part is bad advice, but I'd rather have software break from an update than get ransomware'd.