Yes, opposing the establishment of a new state with a new population where someone else already lived would have been appropriate in the late 1940s.
Unfortunately it’s 2024 now, Israel does exist and time is linear.
So the only thing that can be done now is to recognize neither Israel nor Palestine should be erased.
(Though pointing out that the latter doesn’t seem to get mentioned here would be appropriate.)
Unfortunately that’s exactly how it works.
Look at any country’s border and tell me which ones weren’t established by violence.
The actual question is, what alternative to accepting Israel’s existence would you propose. Because forcefully removing them would just be one more crime.