OK, so a /48 has 50% more bits than a /32. On the other hand,
I've heard no *major* problems with end users getting their /32 from
their provider, and there's 65,536 more /48s. Also, remember that many
end users are getting *multiple* IP's from their provider for SOHO use,
and they'll only need one /48.
A problem with this reasoning is that it makes a lot of questionable
assumptions about who needs how many addresses ... assumptions that will
have consequences for many decades to come, even though they will almost
certainly be wrong.
Isn't /48 far too much for one end user? Then again, isn't it far too
little? Who really knows either way? What will the requirements be 30
years from now? Why not resist the engineer's temptation to try to make
all these decisions immediately?
I've always been surprised by how few software engineers are willing to
mark anything "reserved for future use." They feel a compulsion to find
a purpose and allocation for every single bit right now, no matter how
foolish or ill-conceived that might turn out to be twenty years from
now. It's as if leaving a fudge factor for the unknown were some sort
of admission of weakness.