The four episodes that comprise Volume 1 unsurprisingly walk back the Season 4 cliffhanger. Hawkins, Indiana, has not turned into a hellscape of Demogorgons and slimy vines. Instead, the town has been put under military quarantine, occupied by the same foolhardy industrial complex that started this whole mess in the first place. With Matthew Modine’s Dr. Brenner now dead, the deep state’s latest ambassador is Dr. Kay (Linda Hamilton), a scientist and officer who commands an entire base constructed within the Upside Down. Uncle Sam has stapled over most of Vecna’s rifts with crude metal plates, but left just enough open to use for his own ends.

...

As it hurtles toward a final showdown with Vecna, “Stranger Things” is resetting the clock rather than riding its forward momentum.

That's disappointing to hear. I was expecting a proper conclusion after season 4 ending, hoping it fully embraces the consequences of Vecna invading the human world.