Seasonal movie watching?

No.

I used to do this a lot. Halloween themed movies during late September/October. Christmas movies during late November/December. I felt like it wasn't really Halloween unless I watched a certain movie, same with Christmas. I'm not like that now though, I just watch whatever I want, whenever.

For example, You mentioned watching Dazed and Confused in May. That is my ALL TIME favorite movie and I could watch it every single day of the year. :)

Around Christmas I might watch a Christmas themed horror movie, but since the TV network schedules no longer rule the viewing habits. I kind of watch anything whenever.

I do that to a certain extent. Horror and Mystery isn't just saved for October though. I like it any time. I usually save all of the movies like The Ice Storm and Home for The Holidays (Holly Hunter) and anything else that takes place at Thanksgiving time for November. The same with all movies Christmas, in December.
I save Life With Father for Father's Day along with the 50's version of Father of the Bride and Father's Little Dividend.
For Mother's Day, Stella Dallas and I Remember Mama.
Memorial Day? I like The Best Years Of Our Lives.
Easter? The Ten Commandments.
I get lucky with Meet Me In St. Louis. That film covers all four season!😊

I do Halloween and Christmas movie watching. Also, I like to watch scary movies around Friday the 13th, whenever it may be. So more holiday-specific viewing.

Yes!

Jaws, 4th of July
American Graffiti, end of summer
Die Hard, Christmas eve

Absolutely.

I like watching the Karate Kid and Star Trek movies in the summertime and the Rocky and James Bond films in the winter.

When it comes to classic TV viewing, being a fan of Shatner, Norris, and Hasselhoff I enjoy Baywatch in the summer and Knight Rider in the fall and winter, but things like Walker Texas Ranger and Star Trek all year round.