Is it irresponsible for churches to be open during the coronavirus outbreak?

Yes it is. I love the Lord but will not go against the "stay at home".

not only churches- ANY nonessential place of gathering

A church is a group of people, so it doesn't make sense to say it's open or closed. If you're referring to services, then yes, it is irresponsible. You have to make sure people are safe.

Absolutely. It is also stupid, and denies the Christian idea that the believer may communicate directly with God.

Yes........................

No, I don't think so. 
Honestly, sometimes it seems more irresponsible stores from which people buy everyday and need their products on a regular basis to be closed. Or when sellers on purpose rise their price in this situation, when so much people are left without work.
If people going to churches just maintain basic order, and the church follows the basics for disenfection, fresh air and so on...it is acceptable to be open. 
In many countries banks are open too, but people don't say it's irresponsible. Where I live there are literally queques of people in front of the bank every working day. No one ever said it is bad, and I don't see people trying to orientate to online banking more :/

I think it is because congregations could spread the virus. One alternative is to set up a small shrine at home.

IT IS TRUMP HE WAS THINKING IT WAS A HOAX AND HE IS VERY Is it irresponsible for his actions he cared more for his votes then us he will not win and he will not get the votes he had before he let usa down made usa and every where hurt , he is not and will not make usa great again , we need a better real person in the white house
no votes from us and all of the usa will not vote him in again

Yes it is, but it would be okay for them to be open if they don't hold services and restrict entry like shops do.

Let them all go and get it if that is what they want.