The error message that is shown is a summary for all plugins that have been tried. I guess what you suggest is that this error message should not be shown if only one plugin was tried to be loaded and the user already acknowledged that it's not a valid plugin?

yes, the error message shouldn't be shown as I don't want to try the native one ;)
if I say yes and the native one is not working, and only in this case, I should see this error message
If the error message is shown that's could proove that even I say no, this is doing a yes action (to verify with a native one which is working, I think it will be add in the plugins even if I say no, but I don't have a plugin like that I could test with)

Okay. In that case, don't expect this to be fixed anytime soon. It would require changing an unreasonable amount of code for a minor annoyance (the code that displays the first message is in a completely different part of the program than the code that shows the summary in the second message, and the latter doesn't "know" anything about the former). Just don't load invalid plugins for now. ;)