Are special characters in passwords effective at all?

Password security - but please without special characters

Even if not everyone believes me, but yes, I type in my 20+ digit passport by hand. I have never saved a pass in my browser. As rarely as I register with PayPal etc., this does not happen that often.

Since I'm currently on the ESET website, I am reading the following again:
"WARNING

We strongly recommend that you use a strong password that is long enough and contains numbers, special characters, or capital letters. Use a mix of different character types to make life difficult for attackers. "
http://help.eset.com/eis/11.1/de-DE/idh_page_homenetwork_protection.html

But how can you do something like that if that doesn't work !?

At my bank, that's quite a joke (account manager): The passport can be a maximum of 5 characters long, numbers and letters. Upper / lower case is ignored (if I entered an "N" when issuing the passport, for example, it doesn't matter whether I write an "N" or "n" when logging in, BOTH are accepted. I pointed this out to my bank years ago) , nothing has ever changed and that I only have few attempts to log in is true but only for a few minutes (at least when I tried it about 1-2 years ago).

I think at least there are stones put in your way. On the one hand it is said "Take a good and long passport" and then at the same time "only certain or no special characters, case insensitive and oh only a maximum of 20 characters".

Bottom up!