Great comparison and test metrics. It's great to have off-the-shelf utilities like these.
However, there is something I think it's worth sharing. Sometimes developers abuse split functions like these for simple tasks. In a lot of cases it's used simply to later on join the resulting data set with a table for matching values. We had an issue with a database in production that was using too much tempdb space, and the heavy use of split functions was one of the contributors.
As an alternative, consider the following:
declare @value varchar(10) = 'abc',
@valueSet varchar(50) = 'abc,def',
@delimiter char(1) = ','
if concat(@delimiter,@valueSet,@delimiter) like concat('%',@delimiter,@value,@delimiter,'%')
Put this into a function, call it say FnIsValueInSet, and then use it in your WHERE clause instead of joining to a temp table produced from the split string.