Hey! How are you doing. Can you suggest me some good horror movies? Keep in mind that I am not easily scared. So provide me with the absolute best.
Sure, here are a few of the scariest horror movies according to IMDB:

1. The Exorcist (1973), directed by William Friedkin.
When a teenage girl is possessed by a mysterious entity, her mother seeks the help of two priests to save her daughter.

2. The Evil Dead (1981), directed by Sam Raimi
Five friends travel to a cabin in the woods, where they unknowingly release flesh-possessing demons.

3. The Changeling (1980), directed by Peter Medak
After the death of his wife and daughter in a car crash, a music professor staying at a long-vacant Seattle mansion is dragged into a decades-old mystery by an inexplicable presence in the mansion's attic.

4. The Sixth Sense (1999), directed by M. Night Shyamalan
A frightened, withdrawn Philadelphia boy who communicates with spirits seeks the help of a disheartened child psychologist.

5. Psycho (1960), directed by Alfred Hitchcock
A Phoenix secretary embezzles $40,000 from her employer's client, goes on the run and checks into a remote motel run by a young man under the domination of his mother.

6. The Texas Chain Saw Massacre (1974), directed by Tobe Hooper
Five friends head out to rural Texas to visit the grave of a grandfather. On the way they stumble across what appears to be a deserted house, only to discover something sinister within. Something armed with a chainsaw.

7. Pieces (1982), directed by Juan Piquer Simón 
The co-eds of a Boston college campus are targeted by a mysterious killer who is creating a human jigsaw puzzle from their body parts.

8. Lady in White (1988), directed by Frank LaLoggia
An author tells the story of how, as a young boy growing up in a 1960s small town, he was haunted after witnessing the murder of a little girl.

9. It (1990), TV mini series
In 1960, seven pre-teen outcasts fight an evil demon who poses as a child-killing clown. Thirty years later, they reunite to stop the demon once and for all when it returns to their hometown.

10. Rosemary's Baby (1968), directed by Roman Polanski 
A young couple trying for a baby moves into an aging, ornate apartment building on Central Park West, where they find themselves surrounded by peculiar neighbors.
I notice that all of these movies are pretty old, not a single one of them came out in the current millennium. Is there a reason all the movies are old, like a drop off in the quality of movies being produced? What are some popular contemporary horror movies?
While many classic horror films were made decades ago, there have been plenty of great horror movies made in recent years as well. Here are some popular contemporary horror movies from the 2010s and 2020s that you may enjoy:

1. Get Out (2017), directed by Jordan Peele
A young African American man visits his white girlfriend's family estate, only to become ensnared in a more sinister real reason for the invitation.

2. Hereditary (2018), directed by Ari Aster
After the family matriarch passes away, a grieving family is haunted by tragic and disturbing occurrences, and begin to unravel dark secrets.

3. A Quiet Place (2018), directed by John Krasinski
In a post-apocalyptic world, a family is forced to live in silence while hiding from creatures that hunt by sound.

4. Us (2019), directed by Jordan Peele
A family's serene beach vacation turns to chaos when their doppelgängers appear and begin to terrorize them.

5. The Witch (2015), directed by Robert Eggers
A family in 1630s New England is torn apart by the forces of witchcraft, black magic, and possession.

6. Midsommar (2019), directed by Ari Aster
A couple travels to Sweden to visit a rural hometown's fabled mid-summer festival. What begins as an idyllic retreat quickly devolves into an increasingly violent and bizarre competition at the hands of a pagan cult.

7. It Follows (2014), directed by David Robert Mitchell
A teenage girl is plagued by disturbing visions and the inescapable sense that something is following her after a sexual encounter.

8. The Babadook (2014), directed by Jennifer Kent
A single mother and her son are tormented by a monster from a children's book that has come to life.

9. The Conjuring (2013), directed by James Wan
Paranormal investigators Ed and Lorraine Warren work to help a family terrorized by a dark presence in their farmhouse.

10. Train to Busan (2016), directed by Yeon Sang-ho
While a zombie virus breaks out in South Korea, passengers struggle to survive on the train from Seoul to Busan.

These are just a few examples, and there are many other great horror movies from recent years to choose from as well.