Ah. connector-x claims to be able to do a lot. Seems useful if it can actually deliver on that. Good to know that COPY with asyncpg is a quick approach.
In my case, I had parquet to begin with because I accidentally deleted some production data (oopsies) and when you export a snapshot from RDS to S3, it is in Parquet. Thankfully, I now have a few tricks up my sleeve to quickly restore data, but that was stressful for a bit haha