It's a bold move but I don't see it changing the outcome of the ongoing war. If Ukraine could build long-range ballistic missiles in the near future, I think they could regain the advantage even without any nuclear warheads. Nuclear warheads would not be useful without those ballistic missiles.
(What would happen if Ukraine did have nuclear-armed ballistic missiles but Russia refused to withdraw from Ukrainian territory? I don't foresee Ukraine actually nuking Russia, even in those circumstances.)
Most financially secure people still work full time. I suppose that in theory, they're able to quit their jobs without suffering immediate, catastrophic consequences but if they actually did that sort of thing, they wouldn't be financially secure for long.
(In my experience, many financially secure people actually work much more than full time. I think they would be better off if they didn't because at some point time becomes more valuable than money, but they have the sort of personality that compels them to. This is often related to starting out without financial security.)
The very rich can do crazy stuff without consequences but they're such a small part of the population that I don't think comparing oneself to them is useful.