Nothing wrong with using goodbye. Words meanings change all the time.

Even as an Atheist, I have no problem with "merry Christmas" or "holiday". Why would I avoid "goodbye"?

When in parting, I usually tell people to "Have a great day."

I also say it to my cheese, as I grate it over my food, but with a different spelling: "Have a grate day."

I think 450 years is a long enough gap to safely use the word goodbye without anyone thinking we are “closet” Christians.!

Well speaking an an atheist -- the highest grouping on this site -- since the religious origins of the word goodbye ( which I know as I teach English and usually tell students that) is completely irrelevant now, and is not used in any religious way, I have no problem with it. If we went back and researched all of English for words with a religious origin or some origin not acceptable in the new puritanism of woke political correctness, then our language might be gutted. I live in fear that the woke set might do that anyway, but for language origins that relate not so much with religion but their usual political correctness preoccupations.

Interesting discussion, but can’t we just ge back to eating babies?

"As Agnostics, we had best stop using that word ...." (sic)

Wouldn't the agnostic be unable to decide one way or t'other?

So long
See ya tomorrow
Have a nice day.

Many other options.. Bye ☺

God, in the Scandinavian tongues, from which the English word "good" originates, simply means good, as opposed to bad.
Hence, etymologically, goodbye is a contraction of "good things be with ye".

I see it rather as: a 'bye' is a temporary leave of absence, or a pause. So it's like, "In the interval of time we are apart, I hope everything goes well."
I don't CARE if there's an alternative derivation.

Every time a Christian mentions "Saturday" they are unknowingly paying homage to the pagan god Saturn, who ate his sons, thereby sanctioning murder, cannibalism and child abuse and condemning their souls to an eternity in Hades.

OK. In the KJV bible Paul said "I wanted to come to you but I was let." Language changes over time. The word "let" actually meant prevented at the time of this translation.

Maybe we should depart saying...."Take It Slow"

Meanings change: case in point - gay

The Bible talks about eating. As a result in protest I am never eating again. I will ahow those theist!

That's okay, I say, "later tator".

Nah.
I'll argue the point if someone feels truly compelled.

Never knew that. From now on I will say "See you later" Whenever someone sneezes I NEVER say "god bless you" I always say "Gasientite" Note- I can't spell for shit.

The term "good" has grown well beyond its etymological origins. I have a knee-jerk reaction to anything that limits my expression.
I don't think this behavior would strip me of my agnostic cred.

In that context then should we all not cease using phrases such as "Bless you" when someone sneezes, etc, etc?
There are almost countless phrases in common usage that may/may not also have 'religious' connotations IF one where to actually seek solely to find them.
As an Aussie we often get around such 'religiosities' by merely saying things such as " See ya 'round." Catch ya later," " Take it easy," and when someone sneezes I usually use the German saying, "Gesundheit" which simply means "Good Health," another Aussie style greeting when meeting a friend is " How's it hanging, Mate?", to which the usual response is " OH, a bit on the soft side and to the left," though it should only be used when greeting a male friend.

"Godspeed, John Glenn."