The meaning of "greybeard" have moved from being literally, to current be figuratively. It doesn't mean that the person is A) old, B) man C) have a beard and D) that the beard is grey.

It simply means someone experienced/being at something for a long time. The greybeards at a company can be all women of the age 26, but if they been with the company for 5 years when the company got started 5 years ago, they are the greybeards of that company.

Might as well say "veteran" or "old-timer", although "old-timer" would imply actual old age, "veteran" implies nothing like that.

greybeard has always felt like a term of respect to me. personally i think of the type of person who could have been at bell labs in its heydays. definitely could exclude women though.

It's 2022. Men can get pregnant and women can have a beard.

Greybeards is an inclusive term and it's a well known term.

Because it communicates a well understood idea. It is great that we as a society are becoming more conscious about the way we speak, but I feel like your complaints here are aimed anyone who isn't achieving the proper level of 'purity'.