I visited my parents in Zone 6 and noticed daffodils are just starting to
send up shoots. Hyacinth and allium are as well. Some echinacea that I
thought was supposed to die to the ground is showing some new green
buds.

Should they be doing this? Are they using up energy on things that will be killed by the first major snow?

I'd actually considered weed-wacking this area, since the echinacea
and bee balm gets ratty, and I'm concerned about powdery mildew.
Everything I intentionally planted here should die back to the ground in
the winter. Also this spot gets buried in snow drifts when the
driveway is plowed anyway.

Should I be concerned? Should I use a weed wacker, or is it too late?