i don’t understand

What exactly? I should have corrected it to "not to take well TO"
https://ludwig.guru/s/i+don%27t+take+well+to

In many places they give "resent" as a synonym

https://context.reverso.net/перевод/английский-русский/I+don't+take+well

In your examples, it means to not react positively to something

OK, I can delete it, but I can't offer anything better.
My translation isn't far from "to not react positively to something", and in reverso you can see "не нравится", "не люблю", "не одобряю", "не рад".

Do you think "не рад" is better?

The problem isn’t so much your interpretation as it is the original post. TAKE WELL is affirmative, and can refer to several scenarios. For instance, a transplanted organ can take or not take well, a new policy at a company, something you glued together, information you’re trying to learn. There are so many interpretations of the affirmative that I don’t see the use of assuming a negative meaning. If anything, Ann Stepanova should be more specific and give us more to work with!

Well, I just googled - and didn't find any results without 'not'

https://www.google.com/search?q=%22took+well%22&tbm=bks&sxsrf=ALeKk03GrAZl8f8XJmIvL9UOHHM5gkEF9w:1605191298280&ei=gkatX_rZEI2UtQWZh5T4Dw&start=20&sa=N&ved=0ahUKEwj6ooXJm_3sAhUNSq0KHZkDBf84ChDy0wMIjAE&biw=1444&bih=852&dpr=1