I mean.. I don't think its good per se. Just better than the alternative in a society that's already extremely polarized and more or less evenly split. Unless that changes IMHO ideally we'd at least want as much decision making to move to the state level.
> I believe that FPTP inevitably leads to extreme polarization,
There aren't that many datapoints e.g. it hasn't yet happened in Britain (it sort of did in France, although it's more complicated) and I'm not that sure it was entirely true even in the US between 1940 and 1980 either. So I think its hard to prove empirically.
> So it becomes beneficial to use what government power you might have in order to hinder your opponent's
Is it radically different in multiparty systems, though? If you are outside the government coalition you have similar incentives.
I wonder how effective would the Northern Ireland consensus/power-sharing based system if it became more widespread. On one hand it did seemingly led to a huge reduction in political polarization. On the other hand it's not particularly efficient and it's unlikely that any country would implement outside of extreme circumstances/being force to by a third party (unlike in Lebanon where it has failed entirely the conflict in NI was entirely political rather than religious)