Pro: Why should a druid play? Have fun.
The druids are very versatile. They can hurt (called lightning!) and they can heal. They can participate in close combat (Circle of the Mood druids are very good at this), and can cast spells.
Iconically, when you face monsters with full armor, there are metal heat. Freshly cooked dinner, when it becomes an animal form and feels hungry.
All druids are spell casters complete with a full spell progression.. Druids can cast, at high levels, spells like the true resurrection. That makes the party members come back from the dead.
Wild form: from level 2 to 20, the druid can transform into beasts and assume the advantages and characteristics of these beasts. (Large audience like a wolf, walking on roofs like a giant spider, restraining enemies like a big snake, etc.) On the eighth level, the wild form allows animals that swim and fly to have a wild form: you can go anywhere.
A favorite spell is polymorphous organismBecome a T Rex and terrorize your enemies! See all King Kong; Become a giant monkey! For even more fun, turn your allied hobbit into a T Rex and watch him go crazy!
At high levels, there is urban renewal; Earthquake. (I saw that the spell completely destroyed the strength of a Frost Giant)
A variety of spells based on nature, such as tangle or grabbing the vine, let the Druid take advantage of the power of nature to help your group defeat their enemies; Slowed or restricted enemies are easier to defeat in combat. Numerous spells of earth, wind, fire and storm are at your disposal. If you have access to The Xanathar guide for everything, there are even more spells available.
You can cast each druid spell in the book.. Your only difficult option is "which one do I prepare today?" Good problem to have. (Clerics and paladins also meet that decision requirement).
Oh, and talking to animals. Do you have an itch to Dr. Doolittle waiting to be scratched?
Druids have spells that allow them to talk to animals.
The highest level of druid I came to play was level 10: I became elementals of air and earth. Massive fun
With: Why should not a druid play?
You should not play a druid if you do not want to have fun.
I suggest you open the PHB and check each and every druid spell in the book. Then, think about how you can use them.