Those with Edit permission to to your Data Sources can change the connection (e.g. connect the data source to another Google Analytics view, another Google Ads account, or another Google Sheet), refresh fields, and most importantly update credentials of the data sources to their own?
One implication is that if a person leaves your organization and they no more have access to the underlying dataset, and the data source was set to use Owner's Credentials, the report will break until another editor re-connects the data source using their own credentials.
Also, this gives report editors more control over embedded data sources, because report editors, by default, also have edit permission to the data sources that are embedded into the report.
So, depending on how you manage access to your reports and data sources, it might be a good idea to review who has Edit access to your data sources, or decide if you need to swap an embedded data source with a reusable one to have a tighter control on who has Edit access to it and what other users can do with it.
Here's the official Google documentation: