If the government shuts the airport down now for everyone and keeps it shut for a while, that is one thing. If not, the government will not be justified in shutting it just for Uman travel. 

As I said last year, Israel really should not care about people leaving the country. It could care about people coming in to Israel and it can set rules to regulate who comes in - eg only citizens, only vaccinated, quarantine upon return, electronic trackers, etc. The State of Israel can put any requirement it wants on people coming in to Israel as harsh or weak as it decides to go, and the people will have to comply. if Uman is important enough, they will be willing to be vaccinated or to go through quarantine and testing and whatever. 

But to leave? Israel should not care who leaves. It is Ukraine's problem to decide on their end who to let in and who to keep out. if they say we are open for anyone including Uman travelers (a significant number of whom are likely not vaccinated), that is their problem. They should be allowed to go, and upon return will have to deal with whatever requirements Israel decides on.