I think "no wars of conquest" is a bright line that was crossed by Russia, that hasn't been crossed by other nations in a long time. And I think it's important for the whole world to take a stand on that, not just the nation that was invaded. It's not a "random stand."
I find it much easier to take a strong stand on Russia/Ukraine than on Israel/Palestine. The history of Israel/Palestine is much more of a gray area. Palestine has used plenty of aggressive actions and rhetoric that make Israel's actions more understandable (if not justified).
Example of actions: Gaza invaded Israel and killed, raped, and kidnapped civilians on October 7. Ukraine had no such triggering event that caused Russia to invade.
Example of rhetoric: Gaza's political leaders have said they want to destroy Israel. I don't think anyone in power in Ukraine has said they want to destroy the Russian state.
I am amused by my (unpopular and downvoted by now) comment by the scourge of "whataboutism" sparked a discussion, where comments begin with "how about" :-)
That is exactly my point! Saying "but what about" is akin to saying "you shouldn't do anything, because there is another unrelated $thing happening elsewhere". I refuse to follow this line of thinking.