Thank you for all the information you provided about the issue you are experiencing when connecting to Wi-Fi networks that don't require passwords. I found a couple of resources that I think might help with this.
You may want to try creating a new network location first to see if that makes a difference. You can find the steps to do that under the section titled "Making new locations" in the following article:
If you are still not able to connect to Wi-Fi networks that don't require passwords, I recommend reviewing this article:
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