Yep, all on a 2012 MacBook Air. Data size was over 400GB with indexes

Simple queries on indexed columns of the trips table take a minute or two, more complicated queries that require a full sequence scan can take up to a few hours

All on internal storage? What was the max internal storage then, 512GB? Sounds like that's pretty tight, barely possible if you aren't doing anything else that takes up much space.

I wonder if it would be easier to stick the Postgres on a server, maybe AWS or local, and just do the queries from the laptop. Or maybe on a Tmux on the server, so you can let a long query run without having to keep the laptop up.

Yes, the database is all on the machine's local 512 GB hard drive. I did store the downloaded flat text files to an external drive and loaded them into the db from there.