@hypolite @Hypolite Petovan It's not about tone. Your message and the one I quoted send completely different messages:

Your pictures may be not that funny if you can't describe them

vs.

Please consider describing them anyway, because blind people may have a different perspective than you have.

Even without the "please", the second message would be more substantial, more communicative and less arogant than the first.

It is now up to you to decide how you want to communicate further. For my part, I would like you to refrain from unsolicited "wise advice", for example.