>Would you say the big data threshold moves every year?

It moves with Moore's law. Big data is anything that cannot reasonably fit into memory for a single server, so yes that number is well over 1TB now.

I know this isn't the correct definition but I think of "big data" as the set of data which takes me more than 15 minutes to query on average with a moderately complex Postgres SQL join on well indexed information. I use JSONB in Postgres regularly and have indices on that too. So far I have gotten really far with increasing Postgres work_mem to a gig or more, a fast SSD, and strategically placed materialized views. These kinds of operations in Pandas make my computer billow smoke by comparison.

I don’t think many give much thought to what it really means. They just use the term because it sounds cool, either to themselves or to their superiors. Same as with Machine learning.

What used to be 'big data' is now just 'normal data'.

https://didgets.substack.com/p/big-data