In all honesty, Deir Yassin is simply something that doesn't concern me.
After a period of 20+ years with dozens of massacres of Jews and hundreds more attempted from 1920-1948, it is to Israel's great credit that they have exactly one such incident on their record.
I might mention that this was done by a more extreme group(Irgun) disarmed by Israel's own military, or note the nearby massacre of 77 unarmed medical personnel from Mount Scopus(under the eyes of British soldiers!), or the fact there is NO record of a Jewish settlement being overrun and surviving while Israel had a quarter million Arabs in 1951, or that men from Deir Yassin were singled out for mention by the British in anti-Jewish crimes in 1929 and 1936 but what would it matter?
Instead, I note that despite many atrocities and massacres, the Jews never started running in 1948 while the Arabs(not called Palestinians then) did.
Is it because the Arabs in general or that region in particular were somehow lacking in courage? No, of course not.
Is it because they knew that THEY had options and alternatives to desperate(and bloody) final stands such as retreat to neighboring countries and a later return? Almost certainly.
Now, if the Palestinians had realized the level of aid and support they would receive(or the lack thereof) in the future AT THE TIME then I expect things would have been EXTREMELY different but why would anyone die and leave their families at risk to make a difference of a few months for what was assumed to be the same result?