Hi Renegade989,
We appreciate you reaching out to us. We understand that you started experiencing issues connecting to Wi-Fi networks since you installed iPadOS 15.
We’d like to gather additional details that may help us be in a better position to assist you.
Are you receiving an error message when attempting to connect to Wi-Fi network?
Since the examples that you've provided are Wi-Fi networks from coffee shops, do you have the coffee shop's password?
Do you get the coffee shop's landing page that usually displays the coffee shop's terms of use for their network?
In the meantime, we recommend that you update your device to iPadOS 15.1 if you haven't.
While it isn't inherently assured that an update will resolve the issue, updating to the latest version of iPadOS for your device can help isolate potential software issues.
Kindly secure a backup and update.
How to back up your iPhone, iPad, and iPod touch
Update your iPhone, iPad, or iPod touch
Take care!