If people are supposed to work continuously to make a better world and cannot take any time for themselves....then for whom is the world?? Who can enjoy the world then?
BTW, Since Shabat rules are so strict, and Jews cannot do many things they like (travelling, using a PC to chat, and so on), are they allowed to take a vacation for them on another day, besides the Shabat?
The question is, what defines a "vacation"?
For example, Jews who have shops in Buenos Aires, close for Shabat for religious reasons, but also close on Sundays and National Holidays, and take the day off to rest. They may do some work at home, of course. But also practise sports, sightseeing, and so on. Since in modern tmes, this activities involve electricity light, using a car......and they cannot do it on a Shabat.
Regarding Gentiles, if we are supposed to work everyday, then we wouldn't be able to go to a football match, no tourism, no enjoyment..... if being Noahide forbids all sort of rest for us, I doubt even one here would accep it!
But I strongly disagree with the idea that Jew's teaching Gentiles must not rest will bring a Holocaust or increase anti-Semitism. Many cults teach that Mankind is morally forbidden to do many things and noone hates them. Pentecostals here teach that all Mankind is forbidden to listen to secular music, and they haven't ever been attacked for that. Most people simply don't believe in them. And the same would happen to Jews and Noahides, if they say rest is forbidden to Goyim, people won't hate them for that ( esxcept those who are already anti-Semite), but nearly all Goyim won't accept that idea, and will continue to have vacations, plus the fact that they will probably reject also other Noahide commandments