brent Arch based distros are probably the most common with giving you options in Calamares to do online or offline. It is well implemented to give you both options and works really well in my experience.
diagnostics0
In my experience with EndeavourOS which has the option for both online and offline using Calamares, it does generally say time as it is not having to replace/remove anything, as it is fresh installing. It also saves a boot. More than anything, it just ensures that the user is starting off with the latest version.
As for the risk, it would be a lie to say no. However, with Solus, where you have weekly updates versus random time of updates in more frequent rolling updates in Arch-based system, it would far less likely. But again, this is why having the option for offline or online install is ideal.
