Hi @Will ! I concur with @DougBrowning : Contact your Esri representative for details. The answer to your question may vary depending on how you host your layer (ArcGIS Online, ArcGIS Online with Premium Data Store, ArcGIS Enterprise Hosted, ArcGIS Enterprise with a multi-user geodatabase) and what data you are storing (with attachments or without attachments).
If you are going with ArcGIS Online and your survey does not include attachments (photos, videos, file uploads, signatures...) you can easily go into hundreds of thousands of records without blinking. If you plan to upload attachments or are using ArcGIS Enterprise it is best to consult.