I have a couple 2wts and fwiw, never use them "on local Sierra streams"

It seems a hike up a local freestone nearly always involves some point where
I want to use some weight to get down in that "lunker" hole, or a bigger dry
like a cricket, and a true 2wt ( see Bill's comment about rods called 2wt
that cast a heavier line ) will not deal with that

MY favorite "local Sierra streams" rod is an Orvis "Small Stream Special"
.... don't think it's made anymore .. a 5wt ( 4DT ) rod of 7 1/2 feet .... it
does it all in the small stream venue, and small fish don't "feel bigger"
on a 2wt ... than on the right 4/5wt

Now, god forbid that I should discourage anyone from spending on a new rod
.... but, imho, a true 2wt tops out at a short cast with a #14 dry .... if
you want to cast more you will be unhappy