The way Eurovision voting works is that each voter get 20 points to distribute their vote. I suspect most “ordinary” people distribute their points across multiple artists because they can’t decide on one artist, while Israel supporters distribute all their 20 points to Israel.

Then I suspect most people watching Eurovision don’t vote, while most people supporting Israel vote for Eurovision - even if they don’t watch the competition.

I’ve also heard Israel did targeted ad campaigns urging people to vote for Israel.

So I think it’s less of a conspiracy and more of a foul play.