It's not like he changed his tone much. Not that the position on whether Israel's annexations, settlements etc are illegal would have ever been contentious, the bunched underwear really is about tone. He wasn't fired but he was on his way out which was predictable as putting an Estonian in charge in the face of Russian aggression was an important symbolic move, not really a chance of a second term one way or the other. And it's not like Kallas wouldn't be calling for Israel to fucking tone it down.
And probably rightfully so. It is after all diplomacy. You don't say something like that unless you are prepared to sever all ties. Which would also mean to lose all remaining influence you have - and it would also mean effectively abandoning the jewish people in Israel.
Now I don't mean to argue against the fact that Israel is effectively engaging in genocide. But I believe that severing all ties to Israel would neither benefit the Palestinians, nor the Israelians or Europe for that matter.
Borrell, btw, is the guy who skilfully annoyed Chinese envoys by advocating for this thing called socialism we have in the EU, were we give rights to workers, guarantee healthcare, participation, and such things, "really, we are more socialist than you". Before I saw that footage of the Chinese diplomats I would not have believed that humans are physically capable of that amount of pained smiling.