This is really personal preference! We have some customers who are fierce Tent advocates, while others are firmly in Team Umbrella.
We love a beach umbrella for how quick they are to install by yourself, and how little space they take up on the beach.
On the flip side, a beach tent is great for a few kids to hang out under and fab for a day on the beach when all day shade and set up is the goal. We love that you can tweak the canopy position to suit the wind and sun, and they fit in a suitcase so great for a plane flight getaway.