Your post doesn’t make sense.
This is Christmas. Therefore you wish a happy or merry Christmas. It’s also the time for Hanukkah and kwanzaa but people celebrating those traditions do not greet each other with ‘happy holidays’
They greet each other with ‘Happy Hanukkah’ and ‘Happy Kwanzaa’. Just like every other religious festival that is celebrated, you use the name of the festival. You do not disguise and police the name of the festival in order to not offend others or include others. Others who practice a different religion or aren’t religious at all, aren’t offended by the name of the festival celebrated by others.
Hindus should not start using ‘happy lights holiday’ to be more inclusive around the time of Diwali. They shouldn’t feel the need to make non Hindus feel included in their traditions either.
It’s deeply offensive to celebrate the Christmas festival if you cannot bring yourself to use its name. I’m not Christian but I’ve been raised in a culturally Christian country and I celebrate Christmas. If you send a Christmas card, then you are acknowledging that you are participating in the Christmas festival by virtue of sending a Christmas card. So use the traditional salutations. Don’t pretend you’re being inclusive. How can you be inclusive participating in a culturally Christian tradition that has no reverence for other religions/cultures. It makes no sense!
So Happy Christmas 🎄