The items in the readme all read as warnings and disclaimers, not as enforceable terms of the license agreement. It's basically saying everything you do with this is solely at your own risk, and if you use it in production, any liability is on you.

The attribution request is a "should", not a "must", and not part of the license.

Personally, I wouldn't interpret anything in the readme as binding conditions.

The readme stipulates several things which are allowed and not allowed. They are not disclaimers nor advice as worded when I read them. You can't ignore any stated terms and conditions you don't like. The terms an conditions apply no matter where they are written. The readme is no different than any other file, like for example comments in a random source file.

I did not say anything about attribution. GPL3 already requires attribution and is not a problem. Similarly my suggested CC-BY-SA includes BY.

> The readme stipulates several things which are allowed and not allowed.

I mean, not really -- it's mostly just a big disclaimer of liability, and the only time it uses the phrase "not permitted", it's also just amounts to another disclaimer of liability in that it's saying that it's "not permitted" to use the product without assuming full responsibility for the associated risks.