Google Analytics UI indeed has a limit of 10,001 rows for data tables, it is to ensure optimal performance. For workaround, you can try a couple of ways:

1. If you’re doing an analysis, you can try to reduce the size of your dataset by narrowing down your date range.
2. If it is necessary to handle a large dataset, you can make use of the Google Analytics API. The Google Analytics API does help to extract a significant amount of data which can be more than the limited rows.

As for the part of downloading user data and loading it into R, yes, this is doable. You can use Google Analytics Reporting API v4 to query and retrieve data. A library called “googleAnalyticsR” can be used in R to interact with Google Analytics Reporting API. This will save all the data to data frames in your R environment.

Please remember that due to privacy and security reasons, GA does not provide identifiable user-level data. Therefore all data extracted would be aggregated or anonymized.