Here is what I responded to on dev@.
The first commit removes support for M2_HOME in 3.4 completely. The
second commit only renames a variable used in the script. M2_HOME is
just not needed and is even confusing. People relying on M2_HOME should
just setup theire PATH properly, IMHO. That's what most of them do
anyway. You see
almost everywhere. I am pretty sure there are a lot of people who do not
even notice that setting M2_HOME to something not matching theire PATH
is not what they want. Having a 'mvn' script in my PATH and having that
script use a M2_HOME variable to launch something not in my PATH is
flawed. I thought that was the reason for the request to remove that
variable. No big deal reverting those commits, of course.
So +1 for removing that variable completely in 3.4 or whatever version
is appropriate for such a change.