Its all open my friend allow extra time though at the border.
FYI, I had no issues crossing the Polish border to Kaliningrad but was told I could not return to cross back as a USA passport holder, Not sure if thats still the case. So it might still be a one way for USA passports.
@KO11
do You know if US Passport holder with residency permits in the EU can come back?
@Himynameis I dont know. I would assume if youre traveling with a USA passport this would affect you. You can do a little googling and try to find out more or just have a back up plan for leaving. Things are changing quickly at these borders so its hard to say 100%.