For this DataCamp Course, Colin refers to a dataset on this website. But I check it is not what Colin performs.
The data structures of the two datasets with the same name rstudioconf is different.

Here is the dataset from the DataCamp course, https://campus.datacamp.com/courses/intermediate-functional-programming-with-purrr/case-study-09efa607-1838-4f7c-9040-a62b0fdd0b8e?ex=3

> rstudioconf[[1]]
$status_id
[1] "960732355773239296"

$created_at
[1] "2018-02-06 04:30:17"

It is a list object.

Here is the dataset from this link https://github.com/ThinkR-open/datasets/raw/master/%23RStudioConf.RDS.

suppressMessages(library(tidyverse))
rstudioconf <- read_rds("datasets/rstudioconf.rds")
> class(rstudioconf)
[1] "tbl_df"     "tbl"        "data.frame"

It is a data frame object, which is successfully cleaned.