Mint is very boring and middle of the road, exactly as a default recommendation should be. They are also very protective of the user experience. They are unlikely to embarrass me.
Mint has a familiar UX if you are new to Linux. It is not nearly as foreign or locked down as GNOME. It is not as configurable and complex as KDE. There are good GUI tools for most common tasks.
Mint does not change too rapidly or have too many updates but the desktop and tools are kept up-to-date.
They are being very conservative with the Wayland transition. But nobody on Mint is moaning that Wayland is not ready. They are very protective about the user experience.
And there is really no desktop use case that Mint is not suitable for.
I do not use Mint but it is a very solid recommendation for “normal” users.
I think Pop!OS is back to being that too and COSMIC is Wayland only (so no future transition to manage).
Decent point. Not every grandmother is my grandmother. And a 21 year old that has only used phones and tablets to consume content may actually be less tech literate than an older person with no screen experience that knows how to fix their car, blender, or sewing machine.