You can read this into anything.
> - "from the river to the sea" -> implies the destruction of Israel
The Israeli vs. Palestinian conflict is, for the Palestinians, about property rights. And both sides claim the full area between the Jordan river to the Sea. Plenty of groups say the same thing, whether it's the Chinese view on Taiwan ("one China!") or the ISIS view on the Middle East (and half of Europe and Asia..) being "one Ummah" and nobody calls it racist.
The funny part with that is that it's literally just a pun on the original Israeli Likud party slogan of "between the Sea and the Jordan there will only be Israeli sovereignty"[0]. The other day Netanyahu said the same thing with "West of the Jordan river."[1] Is that whatever the Palestinian equivalent of antisemitism is?
> - "keep the world clean" -> seems to imply some sort of "cleansing" of Jews
All the examples I've seen (as stupid as the phrase is, people seem to copy it as if it's witty) have included the Israeli flag. There are plenty of people that roast Turks and Turkey, but the addition of the crescent moon on their flag doesn't turn into a roast on all of Islam.
Israel has intentionally conflated being anti-Jewish with being anti-Israeli so that you can't target the latter, but somehow also rides the wave of Israeli actions can't be attributed to Jews in general. It's a strange take but if anything has led to a rise in actual antisemitism (as in the anti-Jewish variety) it has been that intentional muddying of the waters.
This also isn't to take away from your main point that there is plenty of real antisemitism out there. I'm sure there is, and it's probably underreported if anything. But the majority of the examples given by pro-Israeli groups (chosen only because they're most visible) are not it.
[0] https://www.jewishvirtuallibrary.org/original-party-platform...
[1] https://www.youtube.com/watch?v=RgdFOIiRpr0