Examples of things that would qualify:
- Postponing the election by three months or more (past the full 4-year term) 
- Banning one or more (nontrivial) parties from running (e.g. banning one of the main Arab parties) 
- Introducing significant barriers to voting (e.g. removing voting booths from most Arab towns or making election day not be a holiday) 
This isn't a universal description, but that's the minimum level of severity for this to settle as yes. Will answer whether any other hypotheticals raised in the comments count. I will not be betting in this market.
It's worth considering this proposed law change: banning parties will not require supreme court ruling
https://twitter.com/amsterdamski2/status/1684642253443137536
@AaronKreider This is a market about Israel becoming less democratic than previously. Not about whether Israel is democratic (Israel is a racist apartheid state - of course the US is also a racist very segregated state)