Why I can one click delete digital signature from a protected document?

Good day!

I have signed some test pdf document with a digital signature.

As you can see on a picture the document is totally protected from any modification.

Now I go to a signature panel and rightclick  my signature.

There is  a Clear Signature option, which do what it says - deletes my signature and make document editable again.

So the question is, why the locked down and certified document is 2 clicks away from editing right in your software?

I know, there is plenty shady apps that breaks pdf security in seconds, its a disaster but we live in it.

But how come that your own software is capable of such things?

Best regard, Denis