AFAIK no but the person you responded to is dogwhistling by repeatedly referencing "arab" and "muslim". They're using it to imply that not only does the UN not matter, they're also positioning these words as the implicit enemy.
It's a bad faith way to approach this argument, so asking logical questions won't make a difference and will tire you out. That's the core strategy behind that behaviour.
I think a more charitable read would be they are claiming that Israel's geopolitical rivals have undue influence in certain UN organs and are using that influence to unfairly single out Israel.
Its not exactly a crazy claim. The UN is a political entity, its not above the influence of geopolitics. The former secretary general of the UN, Ban ki moon at one point (quite a while ago now) said that "Decades of political maneuvering have created a disproportionate number of resolutions, reports and committees against Israel".
If Algeria introduced a resolution declaring that the earth was flat and that Israel had flattened it, it would pass by a vote of 164 to 13 with 26 abstentions.
It's a bad faith way to approach this argument, so asking logical questions won't make a difference and will tire you out. That's the core strategy behind that behaviour.