If you are using incremental sync, this issue doesn’t exist anymore, as we now only apply normalization to new or updated data.
If you are using the Full Refresh sync mode, however:
Airbyte ingests data into raw tables and applies the process of normalization if you selected it in the connection page. The normalization runs a full refresh each sync and for some destinations like Snowflake, Redshift, and BigQuery, this may incur more resource consumption and more costs. You need to pay attention to the frequency that you’re retrieving your data to avoid issues.