The authors conducted a series of microbenchmarks as follows:
scans with single predicates with varying selectivity to study the trade-off between the range scan of a B+ tree vs a columnstore scan
sort and group-by queries to study the benefit of the sort order supported by B+ trees (columnstores in SQL Server are not sorted).
update statements with varying numbers of updated rows to analyze the cost of updating the different index types
mixed workloads with different combinations of reads and updates
It’s interesting to read an academic paper covering the topic, particularly when you can confirm that it works well in practice too.