(author here)

It's a tough call. In my experience, sort and dist keys only really work out in < 50% of queries, and it's the other 50% where you judge the performance of your warehouse.

If we had chosen to use sort and dist keys in Redshift, then we would have also used clustering keys in Snowflake, and it probably would have been somewhat of a wash. BigQuery doesn't really have an equivalent feature yet---they have date partitioning, but that's a very narrow special case that won't work for most queries.