From an operational perspective we've had almost 0 issues with BQ, whereas with Redshift we had to constantly keep giving it TLC. Right from creating users /schemas to WLM tuning, structuring files as Parquet for Spectrum access, understanding why and how spectrum performs in different scenarios, etc. everything was a chore. All this redshift specific specialization I was learning was not really contributing to the product in a meaningful way.
Switched to Bq, a year ago, and it's been mostly self driving. the only thing we had to tend to was the slots and bit of a learning curve for the org about partitioning keys (there is a setting in BQ that fails your query IF partition key is not specified)
Having switched to BQ it's really hard for me to imagine going back to Redshift. It almost feels antiquated.