All the acronyms are optional, and all parts of them are optional.
If you don't want to use DD, use D, or dd, or d, or type daughter - it is up to you what you do or don't do. No-one is going to ban you for typing the full thing. If you don't understand a post, then either ask what the poster means, look it up in the acronyms list, or ignore it.
Acronyms have been in use on here ever since the forum began. It is not the old bats getting down there with the youfs, it is how Gransnet posters communicate, and really, it is not rocket science - no more difficult than calling a personal computer a PC or a television a TV. How often do you say you will turn on the TV? Daily?
It is as it is. Should 5,000 people change an established tradition for those who are not yet familiar with it? If you join a gym, you have to learn where the changing rooms are and how to find your way from reception to the pool. Do you ask them to move everything to the car park so that you don't have to think?