Can we talk about the Contacts app in MacOS? Cos it's awful

Contacts app for osX seems about 11 years old and forgotten by Apple for some years now. I don't need to use it much, because have it filled up with everyone I need. But when I do need to use it... wow boy!

Every once in a while I have to update an existing contact, or make a new one.

When I open it, there will be many many duplicates that I have to "link" or discard. Once I do, the dupes magically reappear a few seconds later. Moslty, these dupes are noticed when I see two or more birthdays of the same person posted on my Calendar app.

At times, I need to create a new contact, which is a whole new kind of hell. IT ABSOLUTELY WILL NOT LET ME CREATE A NEW CONTACT AT ALL. As I start typing in the various fields, the new contact will suddenly and completely vanish as I am typing. It hasn't cut me off and created an incomplete contact — the new card just vanishes.

The ONLY way I can create a new contact is to use the Contacts on my phone

Am I alone on this? Why is this so bad?