Do pro Palestine progressives really not know what “From the River to the Sea” means?

I was on r/stickers and I was seeing at first what looked like some awesome pro LGBT stickers but the second picture had 2 stickers I raised my eyebrow with.

One was a “Gays for Palestine” sticker which… as a trans person I REALLY don’t get since it’s like a “Chickens for KFC” sticker. But that is a whole separate can of worms.

The main one I am pointing out was one that used the phrase “From the River to Sea” as a “Free Palestine” message. In the comments a bunch of people were saying they oppose genocide and such but I gotta wonder… do these people not understand what that phrase means… it is literally a rallying cry for the destruction of Israel… like a cry that says “Israel does not deserve to exist.” And I have seen this phrase time and time and time again in pro Palestine protests and rallies. I gotta wonder, do western progressives just… not know or do actually know and don’t care/actually support the message?