I enjoyed "old fashioned" hackathons, which you had 24h to build or play with some technology or API. It has lost its charm (for me)since it moved to be startup-ish like events that you need to pitch a product instead.
I think it will be considered a "blast from the past" at some point, due to the AI era we are getting into.
retro hackathons will replace retro arcades as gen x retires and millenials are 50+ and have money and kids out of the house. haha.