You lose the experience, and you're not going to be first in line for a promotion when you come back after 6 months. Unless you want to go full Harrison Bergeron and mandate that the employer isn't allowed to reward Alice for the work she did while Bob was on paternity leave.
But how much is it paid? If somebody is making six figures, is it going to cover the whole amount? That seems unlikely. If it's a low percentage of the total amount, then it's forcing a big pay cut that families may not be able to afford.
Details vary by country, but in the three countries I've lived in 100% of your salary. It's paid by social security, even if your salary is in the seven figures, then you also paid a high amount to social security to cover for it.
I think the US would have a long way to go before the public would ever accept having 7+ figure salaries paid out of the taxpayer pocket. That's pretty cool that some countries do though I see some of them only offer the 100% to women and not men.
